Space Shuttle Radiator Panel Actuator Assembly, measuring approximately 9.5 x 5.5 x 3, bearing a parts tag reading, “Actuator Radiator Panel, Latch…Contract No. NAS 9-14000, Mfg. P/N 15820-1, Serial No. US105.” Unit is also labeled “Engineering Test” and bears multiple 1979 date stamps. In fine condition. The radiator actuators were utilized to deploy radiator panels for waste heat rejection into space, primarily from the forward Space Shuttle Payload Bay Doors. Six motor-driven latches secured the radiators until the spacecraft achieved orbit; the actuator was energized to deploy the radiator and subsequently to re-secure each panel prior to Space Shuttle de-orbiting and reentry operations.