This is a sole-source procurement for a flight-critical part requiring existing Government source approval, and only pre-approved sources have been solicited. The Government intends to negotiate with only one source, but it will consider proposals from other capable sources submitted within 45 days of the synopsis publication for future consideration. The time required for a new source to gain approval is typically too long to delay an award. The delivery terms are FOB Origin. Prospective bidders who are not approved sources must submit specific source approval information with their proposal.