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                                                                   EXHIBIT 10(n)

                            THE LAMSON & SESSIONS CO.
      SEVENTH AMENDMENT AND WAIVER TO AMENDED AND RESTATED CREDIT AGREEMENT


         This Seventh Amendment and Waiver to Amended and Restated Credit
Agreement (herein, the "Amendment") is entered into as of February 16, 2005,
among The Lamson & Sessions Co., an Ohio corporation (the "Borrower"), the
Guarantors party hereto, the Lenders party hereto, and Harris Trust and Savings
Bank, as Administrative Agent for the Lenders.


                             PRELIMINARY STATEMENTS

         A. The Borrower, the Guarantors, the Lenders and the Administrative
Agent are parties to an Amended and Restated Credit Agreement dated as of
December 15, 2000 (the Amended and Restated Credit Agreement, as the same has
been amended prior to the date hereof, being referred to herein as the "Credit
Agreement"). All capitalized terms used herein without definition shall have the
same meanings herein as such terms have in the Credit Agreement.

         B. The Borrower has requested that the Lenders waive the Borrower's
non-compliance with Section 8.22 of the Credit Agreement (Total Funded
Debt/EBITDA Ratio) for the period ended December 31, 2004, and that certain
provisions of the Credit Agreement be amended, and the Lenders have agreed to do
so on the terms and conditions set forth in this Amendment.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

SECTION 1.    WAIVER.

         The Borrower has advised the Lenders that the Borrower was not in
compliance with Section 8.22 of the Credit Agreement (Total Funded Debt/EBITDA
Ratio) for the fiscal quarter ended December 31, 2004 (the "Existing Default").
The Borrower has requested that the Lenders waive the Existing Default and, by
signing below, the Required Lenders hereby agree to waive the Existing Default
through the period ended December 31, 2004, subject to the satisfaction of the
conditions precedent set forth in Section 3 below. This is a limited waiver for
the uses and purposes set forth above, and shall not apply to any subsequent
periods.

SECTION 2.    AMENDMENTS.

         Subject to the satisfaction of the conditions precedent set forth in
Section 3 below, the Credit Agreement shall be and hereby is amended as follows:

         2.1. Section 8.22 of the Credit Agreement (Total Funded Debt/EBITDA
Ratio) shall be amended and restated in its entirety to read as follows:

                 Section 8.22.    Total Funded Debt/EBITDA Ratio.  The Borrower
              shall not, as of the last day of each fiscal quarter of the

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              Borrower specified below, permit the Total Funded Debt/EBITDA
              Ratio to be more than:

                                                  TOTAL FUNDED DEBT/EBITDA RATIO
        FISCAL QUARTER ENDING ON OR ABOUT:            SHALL NOT BE MORE THAN:
                  March 31, 2005                            3.10 to 1.0
      June 30, 2005, and each fiscal quarter                2.75 to 1.0
                 ending thereafter

         1.2. Section 8.28 of the Credit Agreement (Level of Borrowings) shall
be amended and restated in its entirety to read as follows:

                           Section 8.28.    Intentionally deleted.

         1.3. In addition to the reporting required under Section 8.5 of the
Credit Agreement, the Borrower hereby agrees to deliver to the Administrative
Agent and the Lenders on or before April 30, 2005, a written plan the Borrower
intends to pursue in order to refinance the Obligations on or before the
Termination Date, which plan shall be in form and with such detail (including
timeline of events) as the Administrative Agent may reasonably require.

SECTION 2.    CONDITIONS PRECEDENT.

         The effectiveness of this Amendment is subject to the satisfaction of
all of the following conditions precedent:

         2.1. The Borrower, the Administrative Agent, and the Required Lenders
shall have executed and delivered this Amendment.

         2.2. The Guarantors shall have executed and delivered to the
Administrative Agent their consent to this Amendment in the space provided
below.

         2.3. The Borrower shall have paid to the Administrative Agent for
distribution to each Lender executing and delivering this Amendment on or before
February 16, 2005, a fee equal to 0.20% of the outstanding amount of each such
Lender's Revolving Credit Commitment and Term Loan.

         2.4. Legal matters incident to the execution and delivery of this
Amendment shall be satisfactory to the Administrative Agent and its counsel.

SECTION 3.    REPRESENTATIONS.

         In order to induce the Lenders to execute and deliver this Amendment,
the Borrower hereby represents to the Lenders that as of the date hereof, and
after giving effect to the waiver and amendments provided for in this Amendment,
(a) the representations and warranties set forth



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in Section 6 of the Credit Agreement are and shall be and remain true and
correct (except that the representations contained in Section 6.5 shall be
deemed to refer to the most recent financial statements of the Borrower
delivered to the Lenders) and (b) the Borrower is in compliance with the terms
and conditions of the Credit Agreement and no Default or Event of Default exists
under the Credit Agreement or shall result after giving effect to this
Amendment.

SECTION 4.    MISCELLANEOUS.

         4.1. The Borrower and the Guarantors have heretofore or concurrently
herewith executed and delivered to the Lenders the Mortgages, the Security
Agreement, the Pledge Agreement, and certain other Collateral Documents. The
Borrower and, by signing below, the Guarantors, hereby acknowledge and agree
that the Liens created and provided for by the Collateral Documents continue to
secure, among other things, the Obligations arising under the Credit Agreement
as amended hereby; and the Collateral Documents and the rights and remedies of
the Lenders thereunder, the obligations of the Borrower and the Guarantors
thereunder, and the Liens created and provided for thereunder remain in full
force and effect and shall not be affected, impaired or discharged hereby.
Nothing herein contained shall in any manner affect or impair the priority of
the liens and security interests created and provided for by the Collateral
Documents as to the indebtedness which would be secured thereby prior to giving
effect to this Amendment.

         4.2. Except as specifically waived and amended herein, the Credit
Agreement shall continue in full force and effect in accordance with its
original terms. Reference to this specific Amendment need not be made in the
Credit Agreement, the Notes, or any other instrument or document executed in
connection therewith, or in any certificate, letter or communication issued or
made pursuant to or with respect to the Credit Agreement, any reference in any
of such items to the Credit Agreement being sufficient to refer to the Credit
Agreement as amended hereby.

         4.3. The Borrower agrees to pay on demand all reasonable costs and
expenses incurred by the Administrative Agent in connection with the
negotiation, preparation, execution and delivery of this Amendment, including
the reasonable fees and expenses of counsel for the Administrative Agent.

         4.4. This Amendment may be executed in any number of counterparts, and
by the different parties on different counterpart signature pages, all of which
taken together shall constitute one and the same agreement. Any of the parties
hereto may execute this Amendment by signing any such counterpart and each of
such counterparts shall for all purposes be deemed to be an original. This
Amendment shall be governed by the internal laws of the State of Illinois.


                           [SIGNATURE PAGE TO FOLLOW]



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         This Seventh Amendment and Waiver to Amended and Restated Credit
Agreement is entered into as of the date and year first above written.


                            "BORROWER"

                            THE LAMSON & SESSIONS CO.



                            By /s/ James J. Abel
                               -------------------------------------------------
                               Name  James J. Abel
                                    --------------------------------------------
                               Title Exec. VP & CFO
                                    --------------------------------------------


                            "GUARANTORS"

                            CARLON CHIMES CO.



                            By /s/ James J. Abel
                               -------------------------------------------------
                               Name  James J. Abel
                                    --------------------------------------------
                               Title Vice President, Secretary & Treasurer
                                     -------------------------------------------

                            DIMANGO PRODUCTS CORPORATION



                            By /s/ James J. Abel
                               -------------------------------------------------
                               Name  James J. Abel
                                    --------------------------------------------
                               Title Secretary
                                    --------------------------------------------

                            PYRAMID INDUSTRIES II, INC.



                            By /s/ James J. Abel
                               -------------------------------------------------
                               Name  James J. Abel
                                    --------------------------------------------
                               Title Vice President & Treasurer
                                     -------------------------------------------

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                            "LENDERS"

                            HARRIS TRUST AND SAVINGS BANK, in its individual
                               capacity as a Lender and as Administrative Agent



                            By /s/ Shahrokh Z. Shah
                               -------------------------------------------------
                               Name  Shahrokh Z. Shah
                                    --------------------------------------------
                               Title Managing Director
                                    --------------------------------------------

                            BANK OF AMERICA, N.A.



                            By /s/ Michael D. Hammond
                               -------------------------------------------------
                               Name  Michael Hammond
                                    --------------------------------------------
                               Title Senior Vice President
                                    --------------------------------------------

                            NATIONAL CITY BANK



                            By /s/ Judith M. Kuclo
                               -------------------------------------------------
                               Name  Judith M. Kuclo
                                    --------------------------------------------
                               Title Senior Vice President
                                    --------------------------------------------

                            THE PROVIDENT BANK



                            By /s/ Norman Lange
                               -------------------------------------------------
                               Name  Norman Lange
                                    --------------------------------------------
                               Title Vice President
                                    --------------------------------------------

                            JPMORGAN CHASE BANK, N.A. (formerly known as Bank
                               One, N.A.)



                            By /s/ Phil Duryen
                               -------------------------------------------------
                               Name  Phil Duryen
                                    --------------------------------------------
                               Title First Vice President
                                    --------------------------------------------

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                            THE HUNTINGTON NATIONAL BANK



                            By /s/ Don W. Lambacher
                               -------------------------------------------------
                               Name  Don W. Lambacher
                                    --------------------------------------------
                               Title Senior Vice President
                                    --------------------------------------------

                            FIFTH THIRD BANK



                            By /s/ Roy C. Lanctot
                               -------------------------------------------------
                               Name  Roy C. Lanctot
                                    --------------------------------------------
                               Title Vice President
                                    --------------------------------------------

                            KEYBANK NATIONAL ASSOCIATION



                            By /s/ Leslie A. Jones
                               -------------------------------------------------
                               Name  Leslie A. Jones
                                    --------------------------------------------
                               Title Vice President
                                    --------------------------------------------

                            LASALLE BANK NATIONAL ASSOCIATION



                            By /s/ Robert M. Walker
                               -------------------------------------------------
                               Name   Robert M. Walker
                                    --------------------------------------------
                               Title  Vice President
                                    --------------------------------------------



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