Camco's Double Propane Tank Locking Device secures two propane tanks to your RV to help prevent theft. The locking device works with conventional and Airstream setups and fits ½-inch and 3/8-inch threaded posts. A combination lock provides keyless access. The locking device is constructed of zinc-plated steel and measures 6 13/16-inches (L) x 3 11/16-inches (W) x 2 5/16-inches (H). Product includes (1) ½-inch top plate, (1) 3/8-inch top plate, (1) lock plate and (1) padlock.