From the notice

NSN 7R-5999-016517373-CC, TDP VER 004, QTY 108 EA, DELIVERY FOB ORIGIN. Acquisition/Repair of this item is restricted to Government approved source(s) because the production/repair of this item involves unclassified but militarily sensitive technology (see FAR Subpart 6.3). The subject item requires Government source approval prior to contract award, as the item is flight critical and/or the technical data available has not been determined adequate to support acquisition via full and open competition. Only the source(s) previously approved by the Government for this item have been solicited. The time required for approval of a new source is normally such that an award cannot be delayed pending approval of a new source. If you are not an approved source you must submit, together with your proposal, the information detailed in one of the NAVSUP Weapon Systems Support (NAVSUP WSS) Source Approval Information Brochures listed below. Spares: [link] port/Business-Opps/ Repair: [link] -Weapon-Systems-Support/Business-Opps/ technical data required to be submitted based on your company's experience in production of the same or similar item, or if this is an item you have never made. If your request for source approval is currently being evaluated at NAVSUP WSS submit with your offer a copy of the cover letter which forwarded your request for source approval.

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