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                                                                    Exhibit 4.12

                       LIMITED LIABILITY COMPANY AGREEMENT

                                       OF

                               FASTLANE MERGER LLC

     This Limited Liability Company Agreement (this "Agreement") of Fastlane
Merger LLC (the "Company") is entered into by CSK Auto, Inc., as the sole member
(the "Member"), as of November 17, 2005.

     The Member, by execution of this Agreement, hereby forms a limited
liability company pursuant to and in accordance with the Delaware Limited
Liability Company Act (6 Del.C. Section 18-101, et. seq.), as amended from time
to time (the "Act"), and hereby agrees as follows:

     1. Name. The name of the limited liability company formed hereby is
Fastlane Merger LLC.

     2. Filing of Certificates. Randi Morrison, as an authorized person within
the meaning of the Act, shall execute, deliver and file all certificates (and
any amendments and/or restatements thereof) required or permitted to be filed
with the Secretary of State of the State of Delaware. The Member is authorized
to execute, deliver and file any other certificates, notices or documents (and
any amendments and/or restatements thereof) necessary for the Company to qualify
to do business in any jurisdiction in which the Company may wish to conduct
business.

     3. Purposes. The Company is formed for the object and purpose of, and the
nature of the business to be conducted and promoted by the Company is, engaging
in any lawful act or activity for which limited liability companies may be
formed under the Act.

     4. Powers. In furtherance of its purposes, but subject to all of the
provisions of this Agreement, the Company shall have and may exercise all the
powers now or hereafter conferred by Delaware law on limited liability companies
formed under the Act and all powers necessary, convenient or incidental to
accomplish its purposes as set forth in Section 3.

     5. Principal Business Office. The principal business office of the Company
shall be located at 645 East Missouri Avenue, Suite 400, Phoenix, Arizona 85012,
or at such other location as may hereafter be determined by the Member.

     6. Registered Office. The address of the registered office of the Company
in the State of Delaware is c/o National Registered Agents, Inc., 160 Greentree
Drive, Ste. 101, City of Dover, County of Kent, Delaware 19904.

     7. Registered Agent. The name and address of the registered agent of the
Company for service of process on the Company in the State of Delaware is
National Registered Agents, Inc., 160 Greentree Drive, Ste. 101, City of Dover,
County of Kent, Delaware 19904.

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     8. Member. The name and the mailing address of the Member are as follows:

<TABLE>
<CAPTION>
     Name                      Address
     ----                      -------
<S>              <C>
CSK Auto, Inc.   645 East Missouri Avenue, Suite 400
                        Phoenix, Arizona 85012
</TABLE>

     9. Limited Liability. Except as provided by the Act, the debts, obligations
and liabilities of the Company, whether arising in contract, tort or otherwise,
shall be solely the debts, obligations and liabilities of the Company, and the
Member shall not be obligated personally for any such debt, obligation or
liability of the Company solely by reason of being a member of the Company.

     10. Capital Contributions. The Member is deemed admitted as a member of the
Company upon its execution and delivery of this Agreement. The Member has
contributed the amount in cash set forth on Schedule I hereto, and no other
property, to the Company.

     11. Additional Contributions. The Member is not required to make any
additional capital contribution to the Company. However, the Member may
voluntarily make additional capital contributions to the Company at any time. To
the extent that the Member makes an additional capital contribution to the
Company, the Member shall revise Schedule I hereto.

     12. Allocation of Profits and Losses. For so long as the Member is the sole
member of the Company, the Company's profits and losses shall be allocated
solely to the Member.

     13. Distributions. Distributions shall be made to the Member at the times
and in the aggregate amounts determined by the Member. Notwithstanding any
provision to the contrary contained in this Agreement, the Company shall not
make a distribution to the Member on account of its interest in the Company if
such distribution would violate the Act or other applicable law.

     14. Management. In accordance with Section 18-402 of the Act, management of
the Company shall be vested in the Member. The Member shall have the power to do
any and all acts necessary, convenient or incidental to or for the furtherance
of the purposes of the Company described herein, including all powers, statutory
or otherwise, possessed by members of a limited liability company under the laws
of the State of Delaware. Notwithstanding any other provision of this Agreement,
the Member is authorized to execute and deliver any document on behalf of the
Company without any vote or consent of any other person. The Member has the
authority to bind the Company.

     15. Officers. The Member may, from time to time as it deems advisable,
select natural persons who are employees or agents of the Company and designate
them as officers of the Company (the "Officers") and assign titles (including,
without limitation, President, Vice President, Secretary, and Treasurer) to any
such person. Unless the Member decides otherwise, if the title is one commonly
used for officers of a business corporation formed under the Delaware General
Corporation Law, the assignment of such title shall constitute the delegation to
such person of the authorities and duties that are normally associated with that
office. Any


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delegation pursuant to this Section 15 may be revoked at any time by the Member.
An Officer may be removed with or without cause by the Member.

     16. Other Business Opportunities. The Member and any person or entity
affiliated with the Member may engage in or possess an interest in other
business opportunities or ventures (unconnected with the Company) of every kind
and description, independently or with others, including, without limitation,
businesses that may compete with the Company. Neither the Member or any person
or entity affiliated with the Member shall be required to present any such
business opportunity or venture to the Company, even if the opportunity is of
the character that, if presented to the Company, could be taken by it. Neither
the Company nor any person or entity affiliated with the Company shall have any
rights in or to such business opportunities or ventures or the income or profits
derived therefrom by virtue of this Agreement, notwithstanding any duty
otherwise existing at law or in equity. The provisions of this Section shall
apply to the Member solely in its capacity as member of the Company and shall
not be deemed to modify any contract or arrangement, including, without
limitation, any noncompete provisions, otherwise agreed to by the Company and
the Member.

     17. Exculpation and Indemnification.

          (a) Neither the Member, nor any officers, directors, stockholders,
partners, employees, affiliates, representatives or agents of the Member, or any
officer, employee, representative or agent of the Company, if any, ("Covered
Person") shall be liable to the Company or any other person or entity who is a
party to or is otherwise bound by this Agreement for any loss, damage or claim
incurred by reason of any act or omission performed or omitted by the Covered
Person in good faith on behalf of the Company and in a manner reasonably
believed to be within the scope of the authority conferred on the Covered Person
by this Agreement, except that the Covered Person shall be liable for any such
loss, damage or claim incurred by reason of the Covered Person's gross
negligence or willful misconduct.

          (b) To the fullest extent permitted by applicable law, the Covered
Person shall be entitled to indemnification from the Company for any loss,
damage or claim incurred by the Covered Person by reason of any act or omission
performed or omitted by the Covered Person in good faith on behalf of the
Company and in a manner reasonably believed to be within the scope of the
authority conferred on the Covered Person by this Agreement, except that the
Covered Person shall not be entitled to be indemnified in respect of any loss,
damage or claim incurred by the Covered Person by reason of the Covered Person's
gross negligence or willful misconduct with respect to such acts or omissions;
provided, however, that any indemnity under this Section shall be provided out
of and to the extent of Company assets only, and no member of the Company shall
have personal liability on account thereof.

     18. Assignments. The Member may at any time assign in whole or in part its
limited liability company interest in the Company. If the Member transfers all
of its interest in the Company pursuant to this Section, the transferee shall be
admitted to the Company upon its execution of an instrument signifying its
agreement to be bound by the terms and conditions of this Agreement. Such
admission shall be deemed effective immediately prior to the transfer, and,
immediately following such admission, the transferor Member shall cease to be a
member of the Company.


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     19. Resignation. The Member may at any time resign from the Company. If the
Member resigns pursuant to this Section, an additional member shall be admitted
to the Company upon its execution of an instrument signifying its agreement to
be bound by the terms and conditions of this Agreement. Such admission shall be
deemed effective immediately prior to the resignation, and, immediately
following such admission, the resigning Member shall cease to be a member of the
Company.

     20. Admission of Additional Members. One or more additional members of the
Company may be admitted to the Company with the written consent of the Member
and upon such terms (including with respect to participation in the management,
profits, losses and distributions of the Company) as may be determined by the
Member and the additional persons or entities to be admitted.

     21. Dissolution.

          (a) The Company shall dissolve and its affairs shall be wound up upon
the first to occur of: (i) the written consent of the Member, (ii) any time
there are no members of the Company, unless the Company is continued in
accordance with the Act, or (iii) the entry of a decree of judicial dissolution
under Section 18-802 of the Act.

          (b) In the event of dissolution, the Company shall conduct only such
activities as are necessary to wind up its affairs (including the sale of the
assets of the Company in an orderly manner), and the assets or proceeds from the
sale of the assets of the Company shall be applied in the manner, and in the
order of priority, set forth in Section 18-804 of the Act.

     22. Benefits of Agreement; No Third-Party Rights. The provisions of this
Agreement are intended solely to benefit the Member and, to the fullest extent
permitted by applicable law, shall not be construed as conferring any benefit
upon any creditor of the Company (and no such creditor shall be a third-party
beneficiary of this Agreement), and the Member shall have no duty or obligation
to any creditor of the Company to make any contributions or payments to the
Company.

     23. Severability of Provisions. Each provision of this Agreement shall be
considered severable and if for any reason any provision or provisions herein
are determined to be invalid, unenforceable or illegal under any existing or
future law, such invalidity, unenforceability or illegality shall not impair the
operation of or affect those portions of this Agreement which are valid,
enforceable and legal.

     24. Entire Agreement. This Agreement constitutes the entire agreement of
the Member with respect to the subject matter hereof.

     25. Governing Law. This Agreement shall be governed by, and construed
under, the laws of the State of Delaware (without regard to conflict of laws
principles), all rights and remedies being governed by said laws.

     26. Amendments. This Agreement may not be modified, altered, supplemented
or amended except pursuant to a written agreement executed and delivered by the
Member.


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     IN WITNESS WHEREOF, the undersigned, intending to be legally bound hereby,
has duly executed this Agreement as of the date first set forth above.

                                        CSK AUTO, INC.


                                        By: /s/ Randi Morrison
                                            ------------------------------------
                                        Name: Randi Morrison
                                        Title: Vice President, General Counsel
                                               and Secretary



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                                                                      SCHEDULE I

<TABLE>
<CAPTION>
NAME             CAPITAL CONTRIBUTION
----             --------------------
<S>              <C>
CSK Auto, Inc.           $100
</TABLE>