This is a procurement for 15 units of a flight-critical part that requires Government source approval prior to contract award. Only previously approved sources have been solicited, as the technical data is not adequate for full and open competition. An unapproved source must submit a full source approval request with its proposal, but the approval process is lengthy and typically cannot delay an award. The delivery terms are FOB Origin. Interested parties may identify their capability to provide a commercial alternative within 15 days of this notice.