Garelick Millinium Series Swivel Seat Mount Top Features: Low profile design allows 360 of rotation; Heavy duty anodized aluminum slide plate has standard 5"x12" hole pattern to accommodate standard seat mounting holes; 360 rotation is regulated by dual locking devices - lift the positive lock lever to rotate. Drop the lever to lock in place in 10 increments. Secondary twist control offers variable drag adjustment and can be tightened down to lock in place.; Internal Delrin Bearing Cup provides smooth, gaul-free operation; 360 degree Positive Lock Swivel Spider Mount Silver Powder Coat Finish; Fits all smooth 2 7/8" diameter bases; Installation & Operating Instructions