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                                                                   Exhibit 10.43

                           LOWRANCE ELECTRONICS, INC.
                             2001 STOCK OPTION PLAN

                           SECOND AMENDED AND RESTATED
                        INCENTIVE STOCK OPTION AGREEMENT

         This Second Amended and Restated Incentive Stock Option Agreement (the
"Agreement"), entered into effective as of the 23rd day of April, 2004, amends
and restates that certain Incentive Stock Option Agreement dated July 25, 2001,
between Lowrance Electronics, Inc., an Oklahoma corporation (the "Company"), and
Mark McQuown (the "Participant").

         1. STOCK OPTION PLAN. This Agreement is entered into pursuant to the
terms of the Lowrance Electronics, Inc. 2001 Stock Option Plan, as it may be
amended from time to time (the "Plan"), which is incorporated herein and made a
part hereof for all purposes. To the fullest extent possible, the terms of this
Agreement shall be interpreted in a manner consistent with the terms of the
Plan; however, to the extent that any provision of this Agreement conflicts with
the express terms of the Plan, it is hereby acknowledged and agreed that the
terms of the Plan shall control and, if necessary, the applicable provisions of
this Agreement shall be deemed amended so as to carry out the purpose and intent
of the Plan; provided, however, under no circumstances shall this Agreement be
amended to allow exercise of the Option or any part thereof prior to the
occurrence of the events described in Section 4.

         2. GRANT OF OPTION. The Company hereby grants to the Participant and
the Participant hereby accepts, subject to the terms and conditions hereof and
the approval by the Shareholders of the 2001 Stock Option Plan of Lowrance
Electronics, Inc., the right and option to purchase from the Company (the
"Option") all or any part of an aggregate of 25,000 shares of the Company's
common stock, par value $0.10 per share (the "Common Stock"), at a per share
purchase price equal to Two Dollars and Sixty-Seven cents ($2.67) per share (the
"Exercise Price"), as such shares and Exercise Price may be adjusted in
accordance with the Plan and Section 12 hereof. The Option is intended to be
treated as an Incentive Stock Option under the Plan and Code Section 422, and
not as a nonqualified stock option.

         3. EXPIRATION AND TERMINATION OF THE OPTION. The Option will expire at
the end of business on July 24, 2011 (the "Expiration Date"). The Option may not
be exercised after its expiration.

         4. EXERCISE OF THE OPTION. The Option may be exercised in whole or in
part at any time or times only upon or after the first to occur of the following
events: (a) the occurrence of any transaction by which Darrell J. Lowrance sells
at least 50% of the shares he then owns directly or indirectly, in a private
placement or registered public offering or through Rule 144 sales, provided the
Participant agrees to comply with any lock-up obligation that may be requested
of Participant in connection with any such registered public offering; or (b)
upon the sale by the Company of all or substantially all of the Company's assets
and operations to a third party; or (c) on or after July 24, 2010. Exercise
shall be accomplished by providing the Company with a completed Notice of
Exercise in the form of Exhibit "A" attached hereto, which notice shall be
effective upon payment in full of the Exercise Price and any amounts required
for taxes pursuant to Section 14 below, and the satisfaction of all other
conditions to exercise imposed under this Agreement. If the either of the events
described in clause (a) or clause (b)

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shall occur prior to the Company's annual meeting of shareholders scheduled for
December 11, 2001, the Company agrees to call a special meeting of shareholders
to request approval of the 2001 Stock Option Plan prior to the occurrence of the
event.

         5. PAYMENT OF EXERCISE PRICE. Upon any exercise of the Option, the
total Exercise Price for the number of shares for which the Option is then being
exercised and the amount of any federal, state and local withholding taxes
imposed thereon shall be payable in full to the Company (i) by bank or certified
check, or (ii) by delivery of whole shares of Common Stock owned by the
Participant free and clear of all liens, claims and encumbrances and evidenced
by negotiable certificates, valuing such shares at their Fair Market Value on
the date of exercise, or (iii) by reducing the number of whole shares of Common
Stock otherwise issuable to Participant as a result of the exercise, valuing
such shares at their Fair Market Value on the date of exercise, or (iv) using a
combination of the foregoing forms of consideration.

         6. TRANSFERABILITY OF OPTION. The Option shall not be transferable
otherwise than by will or the laws of descent and distribution, and is
exercisable, during the lifetime of the Participant, only by the Participant,
or, after Participant's death, by his legal representative or the holder of the
Option by will, the laws of descent and distribution, or beneficiary designation
pursuant to Section 8 of this Agreement. Any attempted transfer, assignment,
pledge or other disposition or levy, attachment or similar process with respect
to the Option not specifically permitted herein shall be null and void without
effect.

         7. EFFECT OF TERMINATION OF EMPLOYMENT. In the event the Participant's
employment with the Company terminates for any reason, other than the
Participant's death, the Option shall automatically terminate. In the event of
termination of the Participant's employment as a result of the Participant's
death, the Option shall be exercisable as if the Participant remained employed
by the Company.

         8. BENEFICIARY DESIGNATIONS. The Participant shall file with the
Corporate Secretary of the Company a designation of one or more beneficiaries
(each a "Beneficiary") to whom the Option otherwise exercisable by the
Participant shall be distributed in the event of the death of the Participant
while in the employ of the Company. The Participant shall have the right to
change the Beneficiary or Beneficiaries from time to time; provided, however,
that any change shall not become effective until received in writing by the
Secretary of the Company. If any designated Beneficiary survives the Participant
but dies before receiving all of his benefits hereunder, any remaining benefits
due him shall be distributed to the deceased Beneficiary's estate. If there is
no effective Beneficiary designation on file at the time of the Participant's
death, or if the designated Beneficiary or Beneficiaries have all predeceased
such Participant, the payment of any remaining benefits shall be made to the
Participant's estate.

         9. LIMITATION OF RIGHTS. Nothing in this Agreement or the Plan shall be
construed to:

                  (a) give the Participant any right to be awarded any further
stock options other than in the sole discretion of the Compensation Committee of
the Company Board of Directors;

                  (b) give the Participant or any other person any interest in
any fund or in any specified asset or assets of the Company or any Affiliate; or

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                  (c) confer upon the Participant the right to continue in the
employment or service of the Company or any Affiliate, or affect the right of
the Company or any Affiliate to terminate the employment or service of the
Participant at any time or for any reason.

         10. PREREQUISITES TO BENEFITS. Neither the Participant, nor any person
claiming through the Participant, shall have any right or interest in the Option
awarded hereunder, unless and until all the terms, conditions and provisions of
this Agreement and the Plan which affect the Participant or such other person
shall have been complied with as specified herein.

         11. RIGHTS AS A SHAREHOLDER. Neither the Participant nor the
Participant's legal representative or Beneficiary shall have any rights as a
shareholder of the Company with respect to the shares of Common Stock issuable
upon exercise of this Option unless and until certificates representing such
shares have been delivered pursuant to the terms hereof.

         12. ADJUSTMENTS. If the shares of Common Stock of the Company as a
whole are increased, decreased or changed into, or exchanged for a different
number or kinds of shares or securities of the Company, whether through merger,
consolidation, reorganization, recapitalization, reclassification, stock
dividend, stock split, combination of shares, exchange of shares, change in
corporate structure or the like, an appropriate and proportionate adjustment
shall be made in the number, kinds and exercise price of shares subject to this
Option. Any such adjustment, however, shall be made without a change in the
total exercise price of the shares underlying the Option. Further, no issuance
by the Company of options, warrants, or shares of stock of any class, including
securities convertible into shares of stock of any class or securities upon the
conversion of such convertible securities or the exercise of any options or
warrants, shall affect, and no adjustment by reason thereof shall be made with
respect to, the number or Exercise Price of shares underlying the Option.

         13. SUCCESSORS AND ASSIGNS. This Agreement shall bind and inure to the
benefit of and be enforceable by the Participant, the Company and their
respective permitted successors and assigns (including personal representatives,
heirs and legatees), except that the Participant may not assign any rights or
obligations under this Agreement except to the extent and in the manner
expressly permitted herein.

         14. FEDERAL AND STATE TAXES. Participant agrees to pay to the Company,
or to make arrangements satisfactory to the Committee to pay to the Company, as
provided in this Option, all federal, state, or local taxes of any kind imposed
on the Participant and required by law to be withheld by the Company in
connection with the transactions contemplated by this Agreement.

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         15. ENTIRE AGREEMENT. This Agreement supersedes all prior agreements,
whether written or oral, between the parties with respect to its subject matter
and constitutes a complete and exclusive statement of the terms of the agreement
between the parties with respect to its subject matter.

         16. GOVERNING LAW. This Agreement shall be governed by, construed and
enforced in accordance with the laws of the State of Oklahoma.

                  This Agreement is executed and delivered, in duplicate,
pursuant to the Plan, the provisions of which are incorporated herein by
reference.

                                    "Company"

                                    Lowrance Electronics, Inc.

                                    By:____________________________________
                                          Darrell J. Lowrance, President

                                    "Participant"

                                    _______________________________________
                                    Mark McQuown

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                                   EXHIBIT "A"

                            NOTICE OF EXERCISE UNDER

                        INCENTIVE STOCK OPTION AGREEMENT

To:   Lowrance Electronics, Inc. (the "Company")

From: ________________________________________

Date: ___________________________________

         Pursuant to the Incentive Stock Option Agreement (the "Agreement")
(capitalized terms used without definition herein have the meanings given such
terms in the Agreement) between the Company and myself effective
______________________, I hereby exercise my Option as follows:

         Number of shares of Common Stock I wish to
         purchase under the Option                               ______

         Exercise Price per share                              $ ______

         Total Exercise Price                                  $ ______

         Income Tax Withholding                                $ ______

         Total obligation                                      $ ______


         I hereby represent, warrant, and covenant to the Company that:

         a. I can bear the economic risk of the investment in the Common Stock
resulting from this exercise of the Option, including a total loss of my
investment.

         b. I am experienced in business and financial matters and am capable of
(i) evaluating the merits and risks of an investment in the Common Stock; (ii)
making an informed investment decision regarding exercise of the Option; and
(iii) protecting my interests in connection therewith.

         c. Any subsequent offer for sale or distribution of any of the shares
of Common Stock shall be made only pursuant to (i) a registration statement on
an appropriate form under the Securities Act of 1933, as amended (the
"Securities Act"), which registration statement has become effective and is
current with regard to the shares being offered or sold, or (ii) a specific
exemption from the registration requirements of the Securities Act, it being
understood that to the extent any such exemption is claimed, I shall, prior to
any offer for sale or sale of such shares, obtain a prior favorable written
opinion, in form and substance satisfactory to the

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Committee, from counsel for or approved by the Committee, as to the
applicability of such exemption thereto.

         I acknowledge that I must pay the total Exercise Price in full and make
appropriate arrangements for the payment of all federal, state and local tax
withholdings due with respect to the Option exercised herein, before the stock
certificate evidencing the shares of Common Stock resulting from this exercise
of the Option will be issued to me.

         I elect to pay in full the total Exercise Price for the Option
exercised herein and all federal and state taxes imposed on me and required by
law to be withheld by Company in connection with the exercise of this Option,
through one or more of the following methods:

         1.       I elect to pay $_________ of my obligation by enclosing a
                  check made payable to the Company in the amount of
                  $__________.

         2.       I elect to pay $_________ of my obligation by enclosing
                  certificate number(s) ___________, representing _______ shares
                  of Lowrance Corporation, Inc. Common Stock owned by me free
                  and clear of all liens claims and encumbrances, properly
                  endorsed to the Company (to determine the number shares,
                  divide such amount by the Fair Market Value per share on the
                  date of exercise).

         3.       I elect to pay $_________ of my obligation by reducing the
                  number of shares of Common Stock that would otherwise be
                  issuable to me upon this exercise, by _______ shares (to
                  determine the number of shares, divide such amount by the Fair
                  Market Value per share on the date of exercise).

                                    PARTICIPANT:

                                    ______________________________

                                    RECEIVED BY THE COMPANY:

                                    By:____________________________
                                    Title:_________________________

Date: _______________

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