(a) Agencies required to requisition, exclusively, items listed in the GSA Supply Catalog shall utilize such items in lieu of procuring similar items from other sources when the GSA items will adequately serve the required functional end-use purpose.

(b) When an agency determines that items available from GSA stock will not serve the required functional end-use purpose of the item proposed to be procured, a request to waive the requirement to use this source shall be submitted to GSA for consideration in accordance with the provisions of § 101-26.100-2.