Flange mounts by Shakespeare can be used to attach marine antennas to deck, bulkhead or radar arch. Useful for small antennas, GPS and radar devices. May be used with the Shakespeare Style 4364 Extension Mast. 4" high, standard 1"-14 threads. This mount does not adjust for a slanted surfaces or allow lowering the antenna for fishing, passage under overhangs, etc. Stainless steel construction.