This is a sole-source procurement for a flight-critical part, restricted to Government-approved sources. The Government intends to negotiate with only one source, and while other interested parties may submit capability statements, only previously approved sources have been formally solicited. Unapproved sources must submit a comprehensive source approval package with their proposal, but the approval process is lengthy and may not be completed in time for award. The item is to be delivered FOB Origin. The acquisition is not being conducted using commercial item procedures.