RAM Twist-Lock Composite Suction Mount for Garmin Montana 600 + More (RAP-B-166-GA46) (sku 54918)The RAP B 166 GA46 consists of a 3. 3" diameter suction cup twist lock base, double socket arm and high strength composite cradle. The suction cup, twist lock base is designed to have a strong hold on glass and non porous plastic surfaces, including RAM adhesive disks. Designed into the mount is a 1" diameter patented rubber ball and socket system with adjustment points at both ends of the socket arm; this with a twist of the arm knob, allows you to