PAVS1132 Features: * Mount * Base can be locked into place with either knob or set-screw adjusting option * Knob or set-screw can be selected and installed on either side of ball housing * 0.625" Shafts are easily removed and are interchangeable with any 0.625" shaft * Rectangular AMPS pattern: 1.2" x 1.5" on center * Base footprint has four 0.219" on a 4.23" circle * Made in the USA Dimensions: * Overall rise height: 6"