The main body of the round rail ball mount is made of 6061-T6 aluminum alloy material with CNC machining and iii grade hard anodized surface for durability and reliability in the most demanding environments. TPU over-molded ball head, non-slip and wear-resistant The tube clamp kit comes with four soft rubber ring inserts that provide a snug fit and protect the mounting surface. Rubber ring insert diameters: 1.5" (38.1mm), 1.65" (41.91mm), 1.75" (44.45mm), 1.85" (46.99mm). The rubber ring can be increased or decreased according to the diameter of the round rails. The tube clamp mount have a 2" (50.8mm) diameter mounting hole without the rubber ring insert The bar clamp mount accommodates round rails 1.5 inch (38.1mm) / 1.65 inch (41.91mm) / 1.75 inch (44.45mm) / 1.85 inch (46.99mm) / 2 inch (50.8mm) in diameter. An Allen key is included with the package to facilitate your installation Compatible with RAM Mounts and BRCOVAN any B size 1 inch ball double socket arm. Work for other devices with 1 inch swivel ball mounting pattern. Great for motorcycle phone mounts, tablet mounts, navigation device mounts, action camera mounts, camcorder mounts, rod holders and much more in a wide variety of applications Fits on UTV roll cage, UTV front bumper, ATV roll bar, motorcycle bull bar, off-road vehicle roof rack, Jeep head rack, trucks, even kayak rails and large handlebars that meet the dimensions specified above. Please Note: Before purchasing, please measure the diameter of the mounting rail to confirm whether this ball mount fits your rail The aluminum alloy tube clamp mount with 1'' TPU ball, fit for ATV UTV roll cage diameter 1.5 inch, 1.65 inch, 1.75 inch, 1.85 inch, 2 inch. Compatible with RAM Mounts B size 1'' ball double socket arm. The main body is made of 6061-T6 aluminum alloy material with CNC machining and anodized surface for durability and reliability in the most demanding environments. TPU over-molded ball head, non-slip and wear-resistant.