Heavy Duty Suction Cup Twist Lock Base with 1.5 inch Ball The RAM-224 consists of a 3.25 inch diameter suction cup twist lock base that is connected to the (RAM-238), diamond base with 1.5 inch rubber ball. The suction cup is designed to have an extra strong hold on any smooth non-porous surface, but for best result, mount the suction cup on a dry glass, or a dry non-porous plastic surface.
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