Exhibit 5.1

                      [Letterhead of Debevoise & Plimpton]

                                                               November 17, 1999

GenTek Inc.
Liberty Lane
Hampton, New Hampshire  03842


                       Registration Statement on Form S-4

Ladies and Gentlemen:

               We have acted as special counsel to GenTek Inc. (the "Company"),
and its subsidiaries listed on Annex A hereto (the "Subsidiary Guarantors" and,
together with the Company, the "Registrants") in connection with the preparation
and filing with the Securities and Exchange Commission (the "Commission") under
the Securities Act of 1933, as amended (the "Act"), of a Registration Statement
on Form S-4 (as amended, the "Registration Statement") relating to the proposed
exchange by the Company of $200,000,000 aggregate principal amount of its 11%
Senior Subordinated Notes due 2009, fully and unconditionally guaranteed by the
Subsidiary Guarantors (the "New Notes") for $200,000,000 aggregate principal
amount of its currently outstanding 11% Senior Subordinated Notes due 2009,
fully and unconditionally guaranteed by the Subsidiary Guarantors (the "Old
Notes"). The Old Notes and the New Notes were, or will be, respectively, issued
by the Company pursuant to the Indenture (the "Indenture"), dated as of August
9, 1999, among the Company, the Subsidiary Guarantors party thereto and U.S.
Bank Trust National Association, as trustee.








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               In so acting, we have examined and relied upon the originals, or
copies certified or otherwise identified to our satisfaction, of such records,
documents, certificates and other instruments as in our judgment are necessary
or appropriate to enable us to render the opinion expressed below.

               We are of the opinion that, when the Registration Statement has
become effective under the Securities Act and the New Notes have been issued and
exchanged for the Old Notes in the manner described in the Registration
Statement and the Indenture, the New Notes will be validly issued and will be
valid and legally binding obligations of the Registrants, enforceable against
the Registrants in accordance with their terms, except as may be limited by
bankruptcy, insolvency, reorganization, moratorium or similar laws relating to
or affecting creditors' rights generally or by general principles of equity
(regardless of whether such enforceability is considered in an action at law or
in equity).

               We express no opinion as to the effect of any Federal or state
laws regarding fraudulent transfers or conveyances.

               We express no opinion as to the laws of any jurisdiction other
than the Federal laws of the United States, the laws of the State of New York
and the corporate laws of the State of Delaware.

               We consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the headings "Legal
Matters" in the Prospectus. In giving such consent, we do not hereby concede
that we are within the category of persons whose consent is required under
Section 7 of the Act or the rules and regulations of the Commission thereunder.


                                             Very truly yours,

                                             /s/ Debevoise & Plimpton








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                                                                         Annex A

                              SUBSIDIARY GUARANTORS


General Chemical Corporation
Toledo Technologies, Inc.
Printing Developments, Inc.
Balcrank Products, Inc.
HMC Patents Holding Company Inc.
Waterside Urban Renewal Corporation
Reheis Inc.
Defiance, Inc.
Binderline Draftline, Inc.
Defiance Precision Products, Inc.
Hy-Form Products, Inc.
Defiance Testing and Engineering Services, Inc.
Noma Corporation
PCT Mexico Corporation
Noma O.P. Inc.
Electronic Interconnect Systems Inc.
Defiance Kinematics Inc.
HN Investment Holdings Inc.
PPI Holdings, Inc.