USA 431, also known as Starshield 4-11, is a satellite operated by NROC and manufactured by SPXS. It was launched on October 24, 2024, from AFWTR SLC4E using a Falcon 9 launch vehicle. The spacecraft has dimensions of 0.3 meters in length, a diameter of 4.1 meters, and a span of 29 meters. Its dry mass is 750 kg with a launch mass of 800 kg. USA 431 uses deployable solar arrays for power and has a configuration described as "Starshield bus ?". The mission purpose is unknown but suspected to involve imaging or SIGINT activities. The satellite's shape is noted as "Box + pan", and it carries the Starshield payload.