"The RAM Tough-Claw is the perfect mounting base for quick and easy tool-less installation and removal on round, square, odd shaped rails and bars. The Tough-Claw can be clamped on rails from 0.625"" - 1.5"" outer diameter. Ideal for mounting tablets, action cameras, smartphones, rod holders for rod storage and much more in a wide variety of applications. Perfectly suited for mounting on the yoke of an aircraft, handlebars and seat posts of bicycles, kayak rails, roll bars and much more, the RAM Tough-Claw will soon become another essential RAM component in your collection of mounting options. Clamping Range (Rail/Tube Surfaces): 0.625"" to 1.5"" Clamping Range (Flat Surfaces): 0"" to 1.14"""