Apollo RRT Antenna Hat Coupler Assembly, measuring approximately 9.5″ x 8.5″ x 10″, with a Grumman label on the side, reading: "Assy, Hat Coupler, RRT Antenna, Pt No. LDW410-11961-1-1, Ser. No. g, Contract No. NAS9-1100." The base is stenciled with part numbers "LDW 410M12648-11" and "LDW410-1264701," as well as frequencies for transmitting and receiving. In very good to fine condition. This ground support item would have been used to test the antenna on the Lunar Module.
