Sechan Electronics Inc.,* Lititz, Pennsylvania (N0003921D2002); and Systems Engineering Support Co. Inc.* (SESCo), San Diego, California (N0003921D2003) are awarded a combined $452,850,428 indefinite-quantity/indefinite-delivery multiple award contract (MAC) for Global Positioning System-Based Positioning, Navigation and Timing Service (GPNTS) follow-on hardware production units. GPNTS is used to receive, process and distribute three-dimensional position, velocity, acceleration, attitude, time and frequency in the formats required by shipboard user systems. The contracts include a base ordering period of five years and a three-year option ordering period. No contract funds will be obligated on the basic MAC awards. Contract funds in the amount of $260,140 will be obligated on the first task order under each contract utilizing fiscal 2021 other procurement (Navy) funds. Each contract includes options, which if exercised, would bring the estimated value of each contact to $241,507,812 for Sechan; and $211,342,616 for SESCo. Throughout the duration of the awarded contracts, the total obligated amount on orders for all of the awarded contracts combined will not exceed $241,507,812. Work will be performed in Lititz, Pennsylvania, for Sechan; and San Diego, California, for SESCo. Work is expected to be completed by September 2029 if the option period is exercised. Contract funds will not expire at the end of the current fiscal year. These contracts were competitively procured with six offers received. The Naval Information Warfare Systems Command, San Diego, California, is the contracting activity.