The Department of Defense, through the Defense Logistics Agency (DLA) Aviation at Philadelphia, PA, is seeking to procure 49 units of an oxygen concentrator, identified by NSN 7R-1680-016102324-E7 and reference number 3261180-0102. This procurement requires engineering source approval from the design control activity to ensure the quality of the part, as it is flight critical and the technical data available does not support full and open competition. Interested vendors must be approved sources or submit the necessary documentation for source approval, as outlined in the NAVSUP Weapon Systems Support Source Approval Information Brochures, to be considered for the contract. For inquiries, interested parties can contact Casey Stock at (215) 737-0543 or via email at casey.stock@dla.mil, with proposals due within 45 days of this presolicitation notice.