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                                                                   EXHIBIT 10.18

                                 FIRST AMENDMENT
                                       TO
                              EMPLOYMENT AGREEMENT

      THIS FIRST AMENDMENT is made and entered into as of the 31st day of
December, 2004, by and between Littelfuse, Inc., a Delaware corporation
(the "Company"), and Howard B. Witt (the "Executive");

                                   WITNESSETH:

      WHEREAS, the Company and the Executive have heretofore entered into an
Employment Agreement dated August 8, 2003 (the "Employment Agreement");

      WHEREAS, the term of the Executive's employment with the Company under the
Employment Agreement ends on December 31, 2004, at which time the Executive
intends to retire;

      WHEREAS, the Employment Agreement provides that the Executive will not
compete for a period of two years after his employment with the Company
terminates; and

      WHEREAS, the Company and the Executive wish to extend the non-competition
period for an additional two-year period, all upon the terms and conditions
hereinafter set forth;

      NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged and confessed, the parties hereto hereby agree as follows:

      1. The first sentence of Section 11.1 of the Employment Agreement is
hereby amended in its entirety to read as follows:

            11.1. During the period that the Executive is employed by the
            Company and, unless the Executive terminates his employment for Good
            Reason or the Company terminates his employment other than for
            Cause, for a period of four years commencing January 1, 2005
            (hereinafter said four-year period is referred to as the
            "Restrictive Period"), the Executive agrees that the Executive will
            not (i) own or have any interest, directly or indirectly, in, or act
            as an officer, director, employee, consultant, agent or
            representative of, or assist in any way or in any capacity, any
            Competitor (as such term is hereinafter defined); or (ii) directly
            or indirectly entice, induce or in any manner influence any person
            who is, or shall be, in the service of the Company or any of its
            Affiliates (as such term

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            is hereinafter defined) to leave such service for the purpose of
            owning or having any interest, directly or indirectly, in, or being
            employed by or associated with any Competitor.

      2. In consideration for the Executive agreeing to extend the
non-competition period under his Employment Agreement for an additional two
years, the Company agrees to pay to the Executive Two Hundred Thousand Dollars
($200,000) on or before January 15, 2005.

      3. Except as specifically amended hereby, the Employment Agreement shall
remain unchanged and continue in full force and effect.

      IN WITNESS WHEREOF, the parties hereto have executed the First Amendment
as of the day and year first above written.

LITTELFUSE, INC.

By      /s/ Philip Franklin                             /s/ Howard B. Witt
   ----------------------------                       --------------------------
   Its  Vice President                                  Howard B. Witt
       ------------------------
                                       -2-<PAGE>

                                                                   EXHIBIT 10.19

                              CONSULTING AGREEMENT

      THIS AGREEMENT is made and entered into as of the 1st day of January,
2005, by and between LITTELFUSE, INC., a Delaware corporation (the "Company"),
and HOWARD B. WITT (the "Consultant");

                                   WITNESSETH:

      WHEREAS, the Company wishes to retain the services of the Consultant in
connection with its business, all upon the terms and conditions hereinafter set
forth;

      NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged and confessed, the parties hereto hereby agree as follows:

      1. Consulting Period. The Company agrees to retain the consulting services
of the Consultant, and the Consultant agrees to render such consulting services
to the Company, subject to the terms and conditions of this Agreement, for the
period beginning January 1, 2005, and ending on December 31, 2006 (the
"Consulting Period").

      2. Consulting Services. During the Consulting Period, the Consultant
agrees to provide such consulting services as may be reasonably requested by the
President or the Board of Directors of the Company from time to time, but in no
event shall the Consultant be required to work more than 40 hours during any
calendar month.

      3. Compensation. During the Consulting Period, the Company agrees to pay
the Consultant $22,916.66 each month as compensation for any consulting services
rendered by the Consultant hereunder.

      4. Serving as a Director. During the Consulting Period, the Consultant
agrees, if requested by the Board of Directors of the Company and elected by the
stockholders of the Company, to serve as a director of the Company. If the
Consultant is elected as a director of the Company, in addition to the
compensation provided for in Section 3 hereof, the Consultant will be paid for
his services as a director the compensation paid to the other non-employee
directors of the Company for their services as directors of the Company

      5. Termination.

      5.1. The Company may terminate this Agreement at any time during the
Consulting Period upon written notice to the Consultant in the event that the
Consultant (i) willfully and

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continually fails to perform the consulting services provided for in this
Agreement (other than any such failure resulting from incapacity due to physical
or mental illness) and such failure is not cured within twenty days to the
reasonable satisfaction of the Board of Directors of the Company; or (ii)
engages in any illegal conduct or gross misconduct which is materially and
demonstrably injurious to the Company.

      5.2. In the event the Company terminates this Agreement pursuant to
Section 5.1 hereof: (i) the Company shall pay to the Consultant the compensation
provided for in Section 3 hereof accrued up to the date of such termination and
shall have no further obligation to pay the Consultant any other compensation
under this Agreement for consulting services with respect to any period before
or after the date of such termination; and (ii) if requested by the Board of
Directors of the Company, the Consultant will resign as a director of the
Company.

      6. Working Facilities. During the Consulting Period, the Consultant shall
be furnished with office space, furnishings, secretarial assistance and such
other facilities and services as the President or the Board of Directors of the
Company shall decide are reasonably necessary for the performance of the
Consultant's consultant services hereunder; provided, however, that the Company
agrees that, so long as Mary Muchoney is reasonably available for this purpose,
the Consultant shall be afforded the part-time administrative and secretarial
services of Mary Muchoney during the Consulting Period.

      7. Expenses. During the Consulting Period, the Company will reimburse the
Consultant for such reasonable business expenses which are incurred by the
Consultant in performing his duties hereunder upon the presentation by the
Consultant from time to time (and at least monthly) of an itemized account of
such expenditures containing such detail as may be reasonably required by the
President or the Board of Directors of the Company.

      8. Independent Contractor. The Consultant shall be and remain an
independent contractor during the Consulting Period and shall not be deemed to
be an employee of the Company for any purpose whatsoever and shall not have, nor
shall the Consultant hold the Consultant out as having, any right, power or
authority to create any contract or obligation, either express or implied, on
behalf of, in the name, or binding upon the Company, unless the Company shall
consent thereto in writing.

      9. Applicable Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of Illinois.

      10. Notices. Each notice, request, demand, approval or other communication
which may be or is required to be given under this Agreement shall be in writing
and shall be deemed to have been properly given when delivered personally at the
address set forth below for the intended party during normal business hours at
such address, when sent by facsimile transmission to the respective facsimile
transmission numbers of the parties set forth below with telephone confirmation
of receipt, or when sent by recognized overnight courier or by United States
registered or certified mail, return receipt requested, postage prepaid,
addressed as follows:

                                      -2-
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                     If to the Company:

                     Littelfuse, Inc.
                     800 E. Northwest Highway
                     Des Plaines, Illinois 60016
                     Attention: President
                     Facsimile: (847) 824-3865
                     Confirm:   (847) 391-0304

                     If to the Consultant:

                     Howard B. Witt
                     93-A Bateman Road
                     Barrington Hills, Illinois 60010
                     Facsimile: _________________
                     Confirm:   (847) 382-5821

Notices shall be given to such other addressee or address, or both, or by way of
such other facsimile transmission number, as a particular party may from time to
time designate by written notice to the other parties hereto. Each notice,
request, demand, approval or other communication which is sent in accordance
with this Section shall be deemed delivered, given and received for all purposes
of this Agreement as of two business days after the date of deposit thereof for
mailing in a duly constituted United States post office or branch thereof, one
business day after deposit with a recognized overnight courier service or upon
confirmation of receipt of any facsimile transmission. Notice given to a party
hereto by any other method shall only be deemed to be delivered, given and
received when actually received in writing by such party.

      11. Retirement. The Company and the Consultant agree that the Consultant
shall be deemed to have retired as an employee of the Company for all purposes
on the day preceding the date of this Agreement.

      12. Indemnification. Each party hereto agrees to indemnify the other party
hereto against, and to hold it or him harmless from, any and all claims,
lawsuits, losses, damages, expenses, costs and liabilities, including, without
limitation, court costs and attorneys' fees, which the other party may sustain
as a result of, or in connection with, either directly or indirectly, the other
party's breach or violation of any of the provisions of this Agreement.

      13. Entire Agreement. This Agreement supersedes all prior agreements and
understandings of, and constitutes the entire agreement between, the parties
hereto with respect to the subject matter hereof and no modification or
amendment of, or waiver under, this Agreement shall be valid unless in writing
and signed by the Consultant and an officer of the Company pursuant to express
authority granted by the Board of Directors of the Company.

                                      -3-
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      14. Counterparts. This Agreement may be executed in two or more
counterparts, all of which taken together shall constitute one and the same
agreement.

      IN WITNESS WHEREOF, the parties hereto have executed this Consulting
Agreement as of the day and year first above written.

LITTELFUSE, INC.

By   /s/ Philip Franklin                          /s/ Howard B. Witt
  -------------------------                   ----------------------------------
Its  Vice President                                   Howard B. Witt
   ------------------------
                                       -4-

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