The RAM-B-149Z-GA46 consists of a zinc coated u-bolt base, double socket arm and high strength composite cradle. Included in this package is hardware that will accommodate rails from 0.50″ to 1.25″ in diameter. The base includes black cover caps to be placed over the exposed ends of the u-bolt. The included composite rail adapter can narrow the rail to a minimum width of 0.5″. The mount is designed with a RAM 1″ diameter patented rubber ball and socket system that has adjustment points at both ends of the double socket arm; this allowing for almost infinite adjustment and perfect viewing angles. Compatible Devices: Garmin Montana 600 Garmin Montana 650 Garmin Montana 650tU-Bolt Dimensions: 0.50″ to 1.25″ Material: High Strength Composite and Powder Coated Marine Grade AluminumBall Size: 1″ Rubber Ball „B” Size Note: Part number reflects product packaged in clear clam shell for store shelf display.Related Links:Garmin Montana New Products PageRAM GPS Mounts.