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                                                                   EXHIBIT 10.28

                                 LEASE GUARANTY

                  In consideration of and as an inducement for the granting,
execution and delivery of that certain Lease Agreement dated as of December 13,
2002 (hereinafter called "Lease"), by WESCO REAL ESTATE IV, LLC, a Delaware
limited liability company ("Landlord"), to WESCO DISTRIBUTION, INC., a Delaware
corporation ("Tenant"), with respect to the Properties (as more particularly
defined and described in the Lease), and in further consideration of the sum of
One Dollar ($1.00) and other good and valuable consideration paid by Landlord to
the undersigned, WESCO INTERNATIONAL, INC., a Delaware corporation
("Guarantor"), intending to be legally bound, hereby guarantees to Landlord the
full and prompt payment when due of all Basic Rent and Additional Rent (as
defined in the Lease) and any and all other sums and charges payable by Tenant
under the Lease, and the full, faithful and prompt performance and observance of
all the covenants, terms, conditions, and agreements therein provided to be
performed and observed by Tenant (the "Obligations"); and Guarantor does hereby
become surety to Landlord for and with respect to all of the Obligations.

                  Guarantor hereby covenants and agrees to and with Landlord
that if default shall at any time be made by Tenant in the payment of any such
rent or other sums or charges payable by Tenant under the Lease or in the
performance of any of the covenants, terms, conditions or agreements contained
in the Lease, Guarantor will forthwith pay such rent or other sums or charges to
Landlord, and any arrears thereof, and will forthwith faithfully perform and
fulfill all of such covenants, terms, conditions and agreements, and will
forthwith pay to Landlord all damages and all costs and expenses that may arise
in consequence of any default by Tenant under the Lease (including, without
limitation, all reasonable attorneys' fees incurred by Landlord or caused by any
such default and/or by the enforcement of this Guaranty).

                  This Guaranty is an absolute and unconditional guaranty of
payment (and not of collection) and of performance and is a surety agreement.
Guarantor's liability hereunder is direct and may be enforced without Landlord
being required to resort to any other right, remedy or security and this
Guaranty shall be enforceable against Guarantor, without the necessity for any
suit or proceedings on Landlord's part of any kind or nature whatsoever against
Tenant, and without the necessity of any notice of non-payment, non-performance
or non-observance or the continuance of any such default or of any notice of
acceptance of this Guaranty or of Landlord's intention to act in reliance hereon
or of any other notice or demand to which Guarantor might otherwise be entitled,
all of which Guarantor hereby expressly waives; and Guarantor hereby expressly
agrees that the validity of this Guaranty and the obligations of Guarantor
hereunder shall in nowise be terminated, affected or impaired by reason of the
assertion or the failure to assert by Landlord against Tenant, of any of the
rights or remedies reserved to Landlord pursuant to the provisions of the Lease.

                  This Guaranty shall be a continuing Guaranty, and (whether or
not Guarantor shall have notice or knowledge of any of the following) the
liability and obligation of Guarantor hereunder shall be absolute and
unconditional and shall remain in full force and effect without regard to, and
shall not be released, discharged or in any way impaired by (a) any amendment or

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modification of, or supplement to, or extension or renewal of, the Lease or any
assignment or transfer thereof; (b) any exercise or non-exercise of any right,
power, remedy or privilege under or in respect of the Lease or this Guaranty or
any waiver, consent or approval by Landlord with respect to any of the
covenants, terms, conditions or agreements contained in the Lease or any
indulgences, forbearances or extensions of time for performance or observance
allowed to Tenant from time to time and for any length of time; (c) any
bankruptcy, insolvency, reorganization, arrangement, readjustment, composition,
liquidation or similar proceeding relating to Tenant, or its properties; (d) any
limitation on the liability or obligation of Tenant under the Lease or its
estate in bankruptcy or of any remedy for the enforcement thereof, resulting
from the operation of any present or future provision of the federal bankruptcy
law or any other statute or from the decision of any court; (e) any sublease or
transfer by Tenant or any assignment, mortgage or pledge of its interest under
the Lease; or (f) any termination of the Lease prior to the expiration of its
Term.

                  All of Landlord's rights and remedies under the Lease and
under this Guaranty are intended to be distinct, separate and cumulative and no
such right and remedy therein or herein mentioned is intended to be in exclusion
of or a waiver of any the others. No termination of the Lease or taking or
recovering of the premises demised thereby shall deprive Landlord of any of its
rights and remedies against Guarantor under this Guaranty. This Guaranty shall
apply to the Obligations pursuant to any extension, renewal, amendment,
modification and supplement of or to the Lease as well as to the Obligations
thereunder during the original Term thereof in accordance with the original
provisions thereof.

                  The Guarantor hereby waives any requirement that the Landlord
protect, secure, perfect or insure any security interest or lien or any property
subject thereto or exhaust any right to take any action against any person or
any collateral (including any rights relating to marshaling of assets).

                  The Obligations will be paid strictly in accordance with the
terms of the Lease, regardless of the value, genuineness, validity, regularity
or enforceability of the Obligations, and of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Landlord with respect thereto. The liability of the Guarantor to
the extent herein set forth shall be absolute and unconditional, not subject to
any reduction, limitation, impairment, termination, defense, offset,
counterclaim or recoupment whatsoever (all of which are hereby expressly waived
by the Guarantor) whether by reason of any claim of any character whatsoever,
including, without limitation, any claim of waiver, release, surrender,
alteration or compromise, or by reason of any liability at any time to the
Guarantor or otherwise, whether based upon any obligations or any other
agreements or otherwise, howsoever arising, whether out of action or inaction or
otherwise and whether resulting from default, willful misconduct, negligence or
otherwise, and without limiting the foregoing irrespective of: (a) any lack of
validity or enforceability of the Lease or of any agreement or instrument
relating thereto; (b) any change in the time, manner or place of payment of, or
in any other term in respect of, all or any of the Obligations, or any other
amendment or waiver of or consent to Obligations, or any other amendment or
waiver of or consent to any departure from the Lease or any other agreement
relating to any Obligations; (c) any increase in, addition to, exchange or
release of, or nonperfection of any lien on or security interest in, any
collateral or any release or amendment or

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waiver of or consent to any departure from or failure to enforce any other
guarantee, for all or any of the Obligations; (d) any other circumstance which
might otherwise constitute a defense available to, or a discharge of, the Tenant
in respect of the obligations of the Guarantor in respect hereof; (e) the
absence of any action on the part of the Landlord to obtain payment for the
Obligations from the Tenant; (f) any insolvency, bankruptcy, reorganization or
dissolution, or any proceeding of the Tenant or the Guarantor, including,
without limitation, rejection of the guaranteed Obligations in such bankruptcy;
or (g) the absence of notice or any delay in any action to enforce any
Obligations or to exercise any right or remedy against the Guarantor or the
Tenant, whether hereunder, under any Obligations or under any agreement or any
indulgence, compromise or extension granted.

                  Guarantor further agrees that, to the extent that the Tenant
or the Guarantor makes a payment or payments to the Landlord, which payment or
payments or any part thereof are subsequently invalidated, declared to be
fraudulent or preferential, set aside and/or required to be repaid to the Tenant
or Guarantor or their respective estate, trustee, receiver or any other party
under any bankruptcy law, state or federal law, common law or equitable cause,
then to the extent of such payment or repayment, this Guaranty and the advances
or part thereof which have been paid, reduced or satisfied by such amount shall
be reinstated and continued in full force and effect as of the date of such
initial payment, reduction or satisfaction occurred.

                  Guarantor shall have no rights (direct or indirect) of
subrogation, contribution, reimbursement, indemnification or other rights of
payment or recovery from any person or entity (including, without limitation,
the Tenant) for any payments made by the Guarantor hereunder, and Guarantor
hereby waives and releases absolutely and unconditionally, any such rights of
subrogation, contribution, reimbursement, indemnification and other rights of
recovery which it may now or hereafter acquire.

                  Guarantor represents and warrants to Landlord that (a) the
execution and delivery of this Guaranty has been duly authorized by the Board of
Directors of Guarantor, (b) the making of this Guaranty does not require any
vote or consent of shareholders of Guarantor and (c) Tenant is a wholly owned
subsidiary of Guarantor.

                  This Guaranty shall be legally binding upon Guarantor and its
successors and assigns and shall inure to the benefit of Landlord and its
successors and assigns. Reference herein to Tenant shall be deemed to include
Tenant and it successors and assigns.

The terms and provisions of this Guaranty shall be governed by the laws of the
State of New York.

                  Guarantor will not enter into any amendment to this Guaranty,
and no such amendment will be effective in any event, without the prior written
consent thereto by the Lender (as defined in the Lease). Guarantor will from
time to time during the Term (as defined in the Lease), promptly following
request of Landlord or Lender, confirm in writing to Landlord and to Lender that
this Guaranty remains in full force and effect in accordance with its terms.

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                  Guarantor and Landlord (by its acceptance of this guaranty)
hereby mutually waive trial by jury in connection with any dispute arising
hereunder.

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                  IN WITNESS WHEREOF, Guarantor, intending to be legally bound
hereby, has caused this Guaranty to be executed by its duly authorized officer
this 13th day of December, 2002.

                                WESCO INTERNATIONAL, INC.

                                By: ____________________________________________
                                    Name:
                                    Title:

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