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                                                                     Exhibit 3.7

                          CERTIFICATE OF INCORPORATION
                                       OF
                         THE COMET PRODUCTS CORPORATION


                                   ARTICLE ONE

          The name of the corporation is The Comet Products Corporation.

                                   ARTICLE TWO

          The address of the corporation's registered office in the State of
Delaware is 9 East Loockerman Street, Suite 1B, in the City of Dover, County of
Kent, 19901. The name of its registered agent at such address is National
Registered Agents, Inc.

                                  ARTICLE THREE

          The nature of the business or purposes to be conducted or promoted is
to engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of the State of Delaware.

                                  ARTICLE FOUR

          The total number of shares of stock which the corporation has
authority to issue is one thousand (1,000) shares of Common Stock, par value one
cent ($0.01) per share.

                                  ARTICLE FIVE

          The name and mailing address of the sole incorporator are as follows:

                            NAME AND MAILING ADDRESS

                                Thaddine G. Gomez
                             200 East Randolph Drive
                                   Suite 5400
                             Chicago, Illinois 60601

                                   ARTICLE SIX

          The corporation is to have perpetual existence.

                                  ARTICLE SEVEN

          In furtherance and not in limitation of the powers conferred by
statute, the board of directors of the corporation is expressly authorized to
make, alter or repeal the by-laws of the corporation.

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                                  ARTICLE EIGHT

          Meetings of stockholders may be held within or without the State of
Delaware, as the by-laws of the corporation may provide. The books of the
corporation may be kept outside the State of Delaware at such place or places as
may be designated from time to time by the board of directors or in the by-laws
of the corporation. Election of directors need not be by written ballot unless
the by-laws of the corporation so provide.

                                  ARTICLE NINE

          To the fullest extent permitted by the General Corporation Law of the
State of Delaware as the same exists or may hereafter be amended, a director of
this corporation shall not be liable to the corporation or its stockholders for
monetary damages for a breach of fiduciary duty as a director. Any repeal or
modification of this ARTICLE NINE shall not adversely affect any right or
protection of a director of the corporation existing at the time of such repeal
or modification.

                                   ARTICLE TEN

          The corporation expressly elects not to be governed by Section 203 of
the General Corporation Law of the State of Delaware.

                                 ARTICLE ELEVEN

          The corporation reserves the right to amend, alter, change or repeal
any provision contained in this certificate of incorporation in the manner now
or hereafter prescribed herein and by the laws of the State of Delaware, and all
rights conferred upon stockholders herein are granted subject to this
reservation.

          I, THE UNDERSIGNED, being the sole incorporator hereinbefore named,
for the purpose of forming a corporation pursuant to the General Corporation Law
of the State of Delaware, do make this certificate, hereby declaring and
certifying that this is my act and deed and the facts stated herein are true,
and accordingly have hereunto set my hand on the 29th day of March, 2004.


                                        /S/ THADDINE G. GOMEZ
                                        ---------------------
                                        Thaddine G. Gomez
                                        Sole Incorporator