This is a sole source procurement for four units of an ESM Receiver Processor, with the government lacking sufficient data to contract with any source other than the current one. The item is subject to Free Trade Agreements and the WTO Government Procurement Agreement. Offerors must be approved sources or submit all required source approval data as detailed in the NAVSUP WSS Source Approval Brochure, or their proposals will not be considered. Inquiries regarding this notice can be directed to the specified Navy contact via email. No budget, timeline, or performance location is provided.