Park Tool Extreme Range Clamp Our most versatile clamp the 100-7X fits all PRS-2,3 and 4 repair stands (including OS models) and works on nearly any bike no matter the size and shape of the frame tube Durable screw type adjustment system provides years of dependable service Clamps round square rectangular and aero shaped tubes from 7/8" to 4" (23mm to 102mm) Quick release pivot system allows clamping of top and bottom or left and right sides of tubes Adjustable clamping pressure prevents damage to thin-wall tubes