RAM Mounts RAM 3.3in. Diameter Suction Cup Twist Lock Base with 1in. Ball RAM-B-224-1U Consists of a 3.3in. twist lock suction cup base that is connected to the RAM-B-238U diamond base with 1in. rubber ball. The suction cup is designed to have an extra strong hold on any smooth, non-porous surface. For best results mount the suction cup on glass or non-porous plastic surface.