The Charles Stark Draper Laboratory, Cambridge, Massachusetts, is awarded a $161,059,197 option under modification (P00001) to a previously awarded cost-plus-incentive-fee, cost-plus-fixed-fee contract (N00030-21-C-0008) to provide design analysis, testing, procurement, and manufacturing of circuit card assemblies, interferometric fiber optic gyros, accelerometers, and material for service life related upgrades of inertial measurement units (IMU), electronic assemblies (EA), electronic modules (EM), and MK6 guidance system-related components. The contract provides the labor and consumable material required to meet approved drawings for the guidance subsystem’s ongoing Strategic Systems Program Alteration (SPALT) of MK6 MOD I guidance systems and MK6 MOD I SPALT material procurements. The contract also provides for the procurement of end item material required to perform the MOD I SPALT of the MOD 0 guidance systems and the failure verification, test, repair, and re-certification of IMUs, EAs, EMs, and other MK6 guidance system-related components. Work will be performed in Cambridge, Massachusetts (25.1%); Pittsfield, Massachusetts (37%); Clearwater, Florida (32.3%); and East Aurora, New York (5.6%), with an expected completion date of July 30, 2025. The option will be fully funded with fiscal 2022 and fiscal 2021 weapons procurement (Navy) and United Kingdom funds, obligated at the time of award. No funds will expire at the end of the current fiscal year. This contract was a sole-source acquisition pursuant to 10 U.S. Code 2304(c)(1) and (4). Strategic Systems Programs, Washington, D.C., is the contracting activity.