RAM Mount Base for secure mounting of your RAM Mount bracket system. This robust universal RAM Mount Base of highest quality is compatible with all RAM Mount mounting systems and 100% weatherproof. It can also be used for your own fixtures. The patented RAM Mount double rubber ball system absorbs vibrations from the mount and prevents them from being transmitted to the combined device. UNPKD. RAM 9/16" BALL W/ 1/4"-20 STUD MATERIAL: Powder Coated Marine Grade Aluminum COLOR: Black Powder Coat BALL SIZE: 9/16 Inch Rubber Ball