Medium version designed to quickly clamp to round, square, and odd-shaped rails and bars ranging from 1"" to 1.875"" in outer diameter; rubber pads provide stable gripping and protection of mounting surface. Ideal mounting base for phones, tablets, cameras, rod holders, and much more; includes 1"" B size rubber ball for attachment to RAM double socket arms. Made of high-strength composite and stainless steel hardware for durability and reliability in the most demanding environments. Rail/Tube Clamp Range: 1"" - 1.6"" Diameter; Flat Surface Clamp Range: 0"" - 1.6"". Backed by a lifetime warranty