Panavise 12-Inch Small Foot Slimline Pedestal Mount Concave Standard Foot evenly distributes the mounting load, accommodates slightly irregular surfaces, will not crack, and measures 2.5 x 2.5  (63.5mm x 63.5mm) Overall mount height (including shaft) is 12-Inch (304.8mm) 210 degree Tilt, 360 Turn and 360 Rotation at both ends Aluminum, zinc and steel construction Rectangular AMPS pattern: 30mm x 38mm (1.181-Inch x 1.496-Inch) on center