This is a solicitation for a commercial, off-the-shelf flight-critical part requiring prior Government source approval. Only pre-approved sources have been solicited, and new sources must submit detailed approval information with their proposal, as the approval process is too lengthy to delay an award. The delivery terms are FOB Origin for a quantity of two each. Proposals that do not include all required source approval data will not be considered. The performance location is not specified, and no budget information is provided.