RAM Mount 1" Ball Light Use Surface Mount f/Garmin echo 100, 150, 300c [RAM-B-101-G4]RAM 1" Ball Marine Electronic "LIGHT USE" Mount for the Garmin echo 100, 150 & 300c The RAM B 101 G4 consists of a double socket arm, 2. 5" diameter round base with the universal AMPS hole pattern and round adapter base that attaches directly to the back of the Garmin echo. Designed into the mount is a 1" diameter patented rubber ball and socket system with adjustment points at both socket ends of the arm; this with RAM's rubber ball and socket