Shakespeare"s Style 81 Swivel Mount is a dual-joint, free-pivoting base mount for use with an appropriate Shakespeare upper bracket in deck or side mounting large or small antennas, The mount"s versatile action fits almost any mounting location, and permits easy lowering of the antenna for clearing overhead obstruction, It requires a stand-off upper bracket, The Style 81 Swivel Mount is included in Styles 409 and 452 Mounting Kits, Stainless steel construction, Standard 1""-14 threads, SKU: CBDST2275