This is for the procurement of one unit of a specific NSN part requiring engineering source approval due to its flight-critical nature and limited technical data. The government intends to solicit only with a previously approved source under FAR 6.302-1, as only those sources retain the necessary data and manufacturing knowledge. Alternate sources must qualify through NAVSUP WSS source approval procedures before award can be considered. Applicable military specifications and standards can be obtained via DODSSP or ASSIST-Online. Responses received may influence a future competitive procurement, but the government cannot delay award pending new source approval.