RAM® Flat Surface Mount for Garmin GPSMAP® and Astro Models.
RAM® B-138-GA41... has a double socket arm, 2.5" dia. round base with the universal AMPS hole pattern, diamond shaped adapter base and custom high strength composite base. Designed into the mount is a 1" diameter patented rubber ball and socket system with adjustment points at the base and cradle. With a twist of the arm knob, you can move the flat surface mount to your optimum viewing position.. Ball size 1" rubber ball "B" size.