Exhibit 10.19

                               PURCHASE AGREEMENT

     This Purchase Agreement ("Agreement") is made as of August __,  2012 by and
between The X-Change Corporation,  a Nevada corporation  ("Buyer"),  and 4C Tech
Holdings, Inc., an Alberta corporation ("Seller").

                              PRELIMINARY STATEMENT

     Seller  desires  to  sell,  and  Buyer  desires  to  purchase,  all  of the
outstanding  shares  (the  "Shares")  of Guardian  Telecom,  Inc.  (Guardian)  a
Canadian corporation organized under the laws of Alberta Canada (the "Company"),
on the terms and subject to the conditions set forth in this Agreement.

                                    AGREEMENT

     The parties, intending to be legally bound, agree as follows:

                                    ARTICLE 1
                                   DEFINITIONS

     For the purposes of this  Agreement,  the following terms and variations on
them have the meanings specified in this Article 1:

     "Buyer" is defined in the first paragraph of this Agreement.

     "Buyer  Shares" means newly issued shares of Buyer common stock,  par value
$.001 per share.

     "Closing" means the consummation and completion of the purchase and sale of
the Shares.

     "Closing Date" means the date on which the Closing actually takes place.

     "Company" is defined in the Preliminary Statement.

     "Company  Contract"  means any  Contract (a) under which the Company has or
may acquire  rights,  (b) under  which the  Company is or may become  subject to
Liability  or (c) by which the  Company  or any of its  assets is or may  become
bound.

     "Consent"  means  any  approval,  consent,  ratification,  waiver  or other
authorization.

     "Contemplated Transactions" means all of the transactions to be carried out
in  accordance  with this  Agreement,  including  the  purchase  and sale of the
Shares,  the  performance by the parties of their other  obligations  under this
Agreement.

                                       1

     "Contract" means any contract, agreement, commitment, understanding, lease,
license, franchise, warranty, guaranty, mortgage, note, bond or other instrument
or  consensual  obligation  (whether  written  or oral and  whether  express  or
implied) that is legally binding.

     "Contravene" -- an act or omission would "Contravene"  something if, as the
context requires:

     (a) the act or omission  would  conflict  with it,  violate it, result in a
breach or  violation  of or failure to comply with it, or  constitute  a default
under it;

     (b) the act or omission  would give any  Governmental  Body or other Person
the right to challenge,  revoke, withdraw,  suspend, cancel, terminate or modify
it, to  exercise  any  remedy or obtain  any  relief  under it, or to  declare a
default or accelerate the maturity of any obligation under it; or

     (c) the act or omission  would result in the creation of an  Encumbrance on
the stock or assets of the Company.

     "Encumbrance" means any charge, claim, mortgage, servitude, easement, right
of way,  community  or other  marital  property  interest,  covenant,  equitable
interest,  license,  lease or other possessory interest,  lien, option,  pledge,
security  interest,  preference,  priority,  right of first  refusal  or similar
restriction.

     "Financial Statements" is defined in Section 3.4.

     "GAAP"  means  generally  accepted  accounting   principles  for  financial
reporting in the United States.

     "Governing  Document"  means any charter,  articles,  bylaws,  certificate,
statement,  statutes  or  similar  document  adopted,  filed  or  registered  in
connection with the creation,  formation or  organization of an entity,  and any
Contract among all equityholders, partners or members of an entity.

     "Governmental   Authorization"  means  any  Consent,   license,  permit  or
registration issued,  granted, given or otherwise made available by or under the
authority of any Governmental Body or pursuant to any Law.

     "Governmental  Body" means any (a) nation,  region,  state,  county,  city,
town,  village,  district or other  jurisdiction,  (b)  federal,  state,  local,
municipal,  foreign or other government,  (c) governmental or quasi-governmental
authority of any nature (including any governmental agency,  branch,  department
or  other  entity  and  any  court  or  other   tribunal),   (d)   multinational
organization,  (e) body exercising, or entitled to exercise, any administrative,
executive,  judicial,  legislative,  police,  regulatory or taxing  authority or
power of any nature, or (f) official of any of the foregoing.

                                       2

     "Knowledge"  means,  with  respect to Seller,  the actual  knowledge  after
reasonable  investigation of Seller or of the Company's  directors,  officers or
senior managerial employees.

     "Law" means any  constitution,  law,  statute,  treaty,  rule,  regulation,
ordinance,  code,  binding  case law,  principle  of common law or notice of any
Governmental Body.

     "Liabilities"  includes  liabilities or obligations of any nature,  whether
known or unknown,  whether absolute,  accrued,  contingent,  choate, inchoate or
otherwise,  whether  due or to become  due,  and  whether or not  required to be
reflected on a financial statement prepared in accordance with GAAP.

     "Order" means any order, injunction,  judgment,  decree, ruling, assessment
or  arbitration  award of any  Governmental  Body or arbitrator and any Contract
with any Governmental Body pertaining to compliance with Law.

     "Ordinary  Course of  Business"  refers to actions  taken in the  Company's
normal  operation,  consistent  with its past  practice  and having no  material
adverse  effect on the  financial  or other  condition,  results of  operations,
assets, Liabilities, equity, business or prospects of the Company.

     "Person"  refers to an  individual or an entity,  including a  corporation,
share company,  limited  liability  company,  partnership,  trust,  association,
Governmental  Body or any other body with legal  personality  separate  from its
equityholders or members.

     "Proceeding"   means   any   action,   arbitration,   audit,   examination,
investigation,   hearing,   litigation   or  suit  (whether   civil,   criminal,
administrative,  judicial or  investigative,  whether  formal or  informal,  and
whether public or private) commenced,  brought, conducted or heard by or before,
or otherwise involving, any Governmental Body or arbitrator.

     "Purchase Price" is defined in Section 2.2.

     "Securities Act" means the Securities Act of 1933.

     "Securities Exchange Act" means the Securities Exchange Act of 1934.

     "Seller Release" is defined in Section 2.4(a)(ii).

     "Seller" is defined in the first paragraph of this Agreement.

     "Seller's  Disclosure  Schedule"  means the disclosure  schedule  delivered
pursuant to Article 3 by Seller to Buyer  concurrently with the execution of the
Agreement.

     "Shares" is defined in the Preliminary Statement.

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                                    ARTICLE 2
                      SALE AND TRANSFER OF SHARES; CLOSING

2.1 SHARES

     Upon the terms and subject to the conditions  set forth in this  Agreement,
at the Closing,  Seller will sell and  transfer  the Shares to Buyer,  and Buyer
will purchase and acquire the Shares from Seller.

2.2 PURCHASE PRICE

     The purchase  price for the Shares (the  "Purchase  Price") will be paid by
delivery of the $250,000.00 Thirty (30) Day Promissory Note (attached as Exhibit
A), a $750,000.00 90 day Promissory Note (attached as Exhibit B) of the Purchase
Price to Seller at the Closing and the issuance of a One year Promissory note in
the amount of Two Million  ($2,000,000.00)  US Dollar and a $500,000.00  Sixteen
Month  Promissory  Note.  All amounts are in US Dollars and the  issuance of One
Million (1,000,000) shares of Buyer's common stock.

2.3 CLOSING

     The Closing will take place at the offices of Seller,  at 10:00 a.m. (local
time) on the date that is two business days following the satisfaction or waiver
of each of the conditions set forth in Articles 5 and 6, and the Buyers audit of
Guardian unless Buyer and Seller agree otherwise.

     CLOSING DELIVERIES

     At the Closing:

     (a) Seller will deliver to Buyer:

     (i)  certificates  representing  the  Shares,  duly  endorsed  in blank (or
accompanied by duly executed stock powers in blank);

     (ii) a release in the form of Exhibit  2.4(a)(ii)  executed  by Seller (the
"Seller Release");

     (iii) a  certificate  executed  by Seller as to the  accuracy  of  Seller's
representations  and  warranties as of the date of this  Agreement and as of the
Closing in  accordance  with  Section  6.1 and as to their  compliance  with and
performance  of its covenants and  obligations to be performed or complied on or
before the Closing Date in accordance with Section 6.2.

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     (b) Buyer will deliver:

     (i) One Million ($1,000,000.00) US Dollar Promissory note due 90 days after
the closing paid to 4C  Technologies,  Dubai UAE and one Promissory  Note in the
amount of Two Million  ($2,000,000.00)  US Dollars bearing  interest at 4% for a
Three year term and a certificate for One Million  (1,000,000) shares of Buyer's
Common Stock.

     (ii) a certificate executed by the President of Buyer as to the accuracy of
Buyer's  representations  and warranties as of the date of this Agreement and as
of the Closing in accordance  with Section 7.1 and as to its compliance with and
performance of its covenants and obligations to be performed or complied with on
or before the Closing Date in accordance with Section 7.2.

                                    ARTICLE 3
                    REPRESENTATIONS AND WARRANTIES OF SELLER

     Seller represents and warrants to Buyer that:

3.1 ORGANIZATION AND GOOD STANDING

     The Company is a corporation  duly organized,  validly existing and in good
standing under the laws of its jurisdiction of organization, with full corporate
power and  authority to conduct its business as presently  conducted,  to own or
use the properties and assets that it purports to own or use, and to perform all
its obligations under all its Company Contracts.

3.2 ENFORCEABILITY; NO CONFLICT

     (a) Seller and the Company have the absolute and unrestricted right, power,
authority  and  capacity to execute and deliver  this  Agreement  and to perform
their obligations under this Agreement.  Assuming due  authorization,  execution
and delivery of this Agreement by Buyer,  this Agreement  constitutes the legal,
valid and binding  obligation  of Seller and the  Company,  enforceable  against
Seller and the Company in accordance with its terms.

     (b) Seller and the  Company  are not and will not be  required  to give any
notice to any Person or obtain  any  Consent or  Governmental  Authorization  in
connection with the execution and delivery of this Agreement or the consummation
or performance of any of the Contemplated Transactions.

     (c)  Neither  the  execution  and  delivery  of  this   Agreement  nor  the
consummation  or  performance  of  any  of the  Contemplated  Transactions  will
directly or indirectly  (with or without notice or lapse of time) (i) Contravene
any provision of the Governing  Documents of the Company,  (ii)  Contravene  any
Company Contract,  Governmental Authorization,  Law or Order to which Company or
Seller,  or any of the assets owned or used by the Company,  may be subject,  or
(iii)  result in the  imposition  or  creation of any  Encumbrance  upon or with
respect to any of the assets owned or used by the Company.

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3.3 CAPITALIZATION AND OWNERSHIP

     The authorized  equity  securities of the Company consist of _______ shares
of common stock,  par value $________ per share,  of which _________  shares are
issued and  outstanding.  The Shares represent all of the issued and outstanding
shares in the  Company.  Seller is and will be on the  Closing  Date the  record
holders and beneficial owners of the Shares, free and clear of all Encumbrances.
All of  the  outstanding  equity  securities  of  the  Company  have  been  duly
authorized and validly issued and are fully paid and nonassessable. There are no
Contracts relating to the issuance, sale or transfer of any equity securities or
other securities of the Company.

3.4 FINANCIAL STATEMENTS

     Seller has  furnished to Buyer  financial  statements  as of July 31, 2009,
July 31, 2010 and July, 2011 (collectively,  the "Financial Statements"),  which
is in the form of a listing of assets and liabilities.  The Financial Statements
were  prepared  in  accordance  with the books and records of the  Company.  The
Financial  Statements  and notes  thereto are  complete  and fairly  present the
assets,  liabilities  and  financial  condition  of the  Company  as of the date
thereof. There will be no liabilities owed to Seller or Seller's family.

3.5 NO UNDISCLOSED LIABILITIES

     The Company has no Liabilities except for Liabilities reflected or reserved
against in the Financial  Statements,  and current  Liabilities  incurred in the
Ordinary Course of Business since the respective dates thereof.

3.6 CONTRACTS; NO DEFAULTS

     (a) Section 3.6 of Seller's  Disclosure  Schedule  contains an accurate and
complete list of:

     (i) each Company Contract that involves performance of services or delivery
of goods or materials by the Company of an amount or value in excess of $10,000;

     (ii) each Company  Contract  that involves  performance  of services for or
delivery of goods or materials to the Company of an amount or value in excess of
$10,000; and

     (iii) each  Company  Contract  that was not  entered  into in the  Ordinary
Course of Business and that involves the  expenditure  or receipt by the Company
of an amount or value in excess of $10,000.

3.7 LEGAL PROCEEDINGS; ORDERS

     (a) There  exists no pending  Proceedings  (i) by or against the Company or
that  otherwise  relate to or may affect the  business  of, or any of the assets
owned or used by,  the  Company  or (ii)  that  challenge,  or that may have the

                                       6

effect of preventing,  delaying,  making illegal or otherwise  interfering with,
any of the  Contemplated  Transactions.  To  Seller's  Knowledge,  no other such
Proceeding has been threatened, and no event has occurred or circumstance exists
that may  give  rise to or serve  as a basis  for the  commencement  of any such
Proceeding.

     (b) There  exists no  pending  Order to which  the  Company,  or any of the
assets owned or used by the Company, is or has been subject.

3.8 SECURITIES LAW MATTERS

     NONE

3.9 BROKERS OR FINDERS

     Seller has not incurred any  Liability  for  brokerage or finders'  fees or
agents' commissions or other similar payment in connection with the Contemplated
Transactions.

                                    ARTICLE 4
                     REPRESENTATIONS AND WARRANTIES OF BUYER

     Buyer represents and warrants to Seller that:

4.1 ORGANIZATION

     Buyer  is a  corporation  duly  organized,  validly  existing  and in  good
standing under the laws of its jurisdiction of organization.

4.2 ENFORCEABILITY; NO CONFLICT

     (a) Buyer has the absolute and unrestricted  right,  power and authority to
execute and deliver this  Agreement  and to perform its  obligations  under this
Agreement, which actions have been duly authorized and approved by all necessary
corporate action of Buyer. Assuming the execution and delivery of this Agreement
by Seller, this Agreement constitutes the legal, valid and binding obligation of
Buyer, enforceable against Buyer in accordance with its terms.

     (b)  Buyer  is not and  will not be  required  to  obtain  any  Consent  or
Governmental Authorization in connection with the execution and delivery of this
Agreement  or the  consummation  or  performance  of  any  of  the  Contemplated
Transactions.

     (c) Neither the execution  and delivery of this  Agreement by Buyer nor the
consummation  or performance of any of the  Contemplated  Transactions  by Buyer
will give any Person the right to prevent, delay or otherwise interfere with any
of the  Contemplated  Transactions  pursuant  to (i) any  provision  of  Buyer's
Governing  Documents,  (ii) any resolution  adopted by the board of directors or

                                       7

the stockholders of Buyer, (iii) any Law, Order or Governmental Authorization to
which Buyer may be subject or (iv) any  Contract to which Buyer is a party or by
which Buyer may be bound.

4.3 BROKERS OR FINDERS

     Buyer has not  incurred any  Liability  for  brokerage or finders'  fees or
agents' commissions or other similar payment in connection with the Contemplated
Transactions.

                                    ARTICLE 5
                     COVENANTS OF THE PARTIES BEFORE CLOSING

5.1 ACCESS AND INVESTIGATION

     Between the date of this Agreement and the Closing Date and upon reasonable
advance  notice  from  Buyer,  Seller  will,  and will cause the Company to, (a)
afford Buyer full and free access to Company's personnel, properties, Contracts,
books and records,  and other  documents and data, (b) furnish such Persons with
copies of all such Contracts, books and records, and other documents and data as
Buyer may reasonably request,  and (c) furnish such Persons with such additional
financial,  operating  and other data and  information  as Buyer may  reasonably
request.

5.2 OPERATION OF THE BUSINESS OF THE COMPANY

     Between the date of this  Agreement and the Closing Date,  Seller will, and
will cause the Company to, (a) conduct its business only in the Ordinary  Course
of Business,  (b) use their Best Efforts to preserve intact the current business
organization  of the  Company,  keep  available  the  services  of  the  current
officers,  employees  and agents of the  Company,  and  maintain  relations  and
goodwill with suppliers,  customers, landlords, creditors, employees, agents and
others having  business  relationships  with the Company,  (c) confer with Buyer
concerning  operational  matters of a material  nature and (d) otherwise  report
periodically  to Buyer  concerning  the status of the business,  operations  and
finances of the Company.

5.3 REQUIRED APPROVALS

     As  promptly as  practicable  after the date of this  Agreement,  Buyer and
Seller  will,  and Seller will cause the Company to, make all filings  that they
are required by Law to make to consummate the Contemplated Transactions. Between
the date of this  Agreement  and the Closing  Date,  Buyer and Seller will,  and
Seller  will cause the  Company  to,  (a)  cooperate  with the other  Party with
respect  to all  filings  that such  Party  elects to make or that such Party is
required by Law to make in connection with the  Contemplated  Transactions,  and
(b) cooperate with Buyer in obtaining any Governmental Authorizations.

                                       8

5.4 [SHAREHOLDER APPROVAL

     BUYER DOES NOT REQUIRE SHAREHOLDER APPROVAL

                                    ARTICLE 6
               CONDITIONS PRECEDENT TO BUYER'S OBLIGATION TO CLOSE

     Buyer's  obligation  to purchase  the Shares and to take the other  actions
required to be taken by Buyer at the Closing is subject to the satisfaction,  on
or before the Closing Date, of each of the  following  conditions  (any of which
may be waived by Buyer, in whole or in part):

6.1 ACCURACY OF REPRESENTATIONS

     All  of  Seller's   representations   and   warranties  in  this  Agreement
(considered both collectively and  individually)  must have been accurate in all
material respects as of the date of this Agreement,  and must be accurate in all
material respects as of the Closing Date as if then made.

6.2 SELLERS' AND COMPANY'S PERFORMANCE

     All of the covenants and obligations that Seller and Company is required to
perform or to comply with under this  Agreement  on or before the  Closing  Date
(considered both  collectively and  individually)  must have been duly performed
and complied with in all material respects.

6.3 STOCKHOLDER APPROVAL

     The  Buyer's  stockholders  if  required  by the Bylaws of Buyer shall have
approved the Contemplated Transactions.

                                    ARTICLE 7
              CONDITIONS PRECEDENT TO SELLER'S OBLIGATION TO CLOSE

     Seller's  obligation  to sell  the  Shares  and to take the  other  actions
required to be taken by Seller at the Closing is subject to the satisfaction, on
or before the Closing Date, of each of the  following  conditions  (any of which
may be waived by Seller, in whole or in part):

7.1 ACCURACY OF REPRESENTATIONS

     All of Buyer's representations and warranties in this Agreement (considered
both  collectively  and  individually)  must have been  accurate in all material

                                       9

respects as of the date of this  Agreement  and must be accurate in all material
respects as of the Closing Date as if then made.

7.2 BUYER'S PERFORMANCE

     All of the covenants and  obligations  that Buyer is required to perform or
to comply with under this  Agreement on or before the Closing  Date  (considered
both collectively and  individually)  must have been performed and complied with
in all material respects.

                                    ARTICLE 8
                                   TERMINATION

8.1 TERMINATION EVENTS

     Subject to Section 8.2,  this  Agreement  may, by notice given before or at
the Closing, be terminated:

     (a) by mutual consent of Buyer and Seller;

     (b) by  Buyer if the  satisfaction  of any  condition  in  Article  6 is or
becomes  impossible  (other than through the failure of Buyer to comply with its
obligations under this Agreement) and Buyer has not waived such condition;

     (c) by Seller  if the  satisfaction  of any  condition  in  Article 7 is or
becomes  impossible (other than through the failure of Seller to comply with its
obligations under this Agreement) and Seller has not waived such condition; and

     (d) by either Buyer or Seller if the Closing has not  occurred  (other than
through the failure of any party seeking to terminate  this  Agreement to comply
fully with its  obligations  under this Agreement) on or before August 31, 2012,
or such later date as Buyer and Seller may agree upon.

8.2 EFFECT OF TERMINATION

     Each party's right of  termination  under Section 8.1 is in addition to any
other rights it may have under this Agreement or otherwise,  and the exercise of
such right of termination will not be an election of remedies. If this Agreement
is terminated pursuant to Section 8.1, all obligations of the parties under this
Agreement  will  terminate;   provided,  however,  that  if  this  Agreement  is
terminated by a party because of the breach of the Agreement by another party or
because one or more of the  conditions to the  terminating  party's  obligations
under this  Agreement is not satisfied as a result of any other party's  failure
to comply with its  obligations  under this Agreement,  the terminating  party's
right to pursue all legal remedies will survive such termination unimpaired.

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                                    ARTICLE 9
                            INDEMNIFICATION; REMEDIES

9.1 SURVIVAL

     All  representations,   warranties,   covenants  and  obligations  in  this
Agreement,  and any other  certificate  or document  delivered  pursuant to this
Agreement  will  survive the Closing and the  consummation  of the  Contemplated
Transactions.

                                   ARTICLE 10
                               GENERAL PROVISIONS

10.1 EXPENSES

     Except as otherwise  expressly  provided in this  Agreement,  each party to
this Agreement will bear its respective expenses incurred in connection with the
preparation,  execution and  performance of this Agreement and the  Contemplated
Transactions, including all fees and expenses of its Representatives.

10.2 FURTHER ACTIONS

     Upon the request of any party to this Agreement, the other parties will (a)
furnish to the  requesting  party any  additional  information,  (b) execute and
deliver,  at their  own  expense,  any  other  documents  and (c) take any other
actions as the requesting party may reasonably require to more effectively carry
out the intent of this Agreement and the Contemplated Transactions.

10.3 ENTIRE AGREEMENT AND MODIFICATION

     This  Agreement  supersedes  all prior  agreements  among the parties  with
respect to its subject matter a complete and exclusive statement of the terms of
the  agreement  between the parties  with  respect to its subject  matter.  This
Agreement may not be amended,  supplemented  or otherwise  modified  except in a
written  document  executed by the party against whose interest the modification
will operate.

10.4 SEVERABILITY

     If a court of competent  jurisdiction holds any provision of this Agreement
invalid or unenforceable,  the other provisions of this Agreement will remain in
full  force  and  effect.  Any  provision  of this  Agreement  held  invalid  or
unenforceable only in part or degree will remain in full force and effect to the
extent not held invalid or unenforceable.

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10.5 GOVERNING LAW

     This  Agreement  will  be  governed  by and  construed  under  the  laws of
California without regard to conflicts of laws principles that would require the
application of any other law.

10.6 COUNTERPARTS

     This Agreement may be executed in two or more counterparts.

     The parties  have  executed  and  delivered  this  Agreement as of the date
indicated in the first sentence of this Agreement.

The X-Change Corporation                     4C Tech Holdings, Inc.


By /s/ R. Wayne Duke                         By /s/ Kamran Bashir
  ---------------------------------            ---------------------------------
  R. Wayne Duke                                Kamran Bashir
  President                                    Chairman of the Board

                                             Guardian Telecom, Inc.


                                             By /s/ Kamran Bashir
                                               ---------------------------------
                                               Kamran Bashir
                                               Chairman of the Board


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