The new model, the two arm pads are made of aluminum alloy trays, they will not bend under the weight of your arm. We use aluminum alloy trays to withstand greater weight and better functionality. Center Clamp Diameter: Fits Handlebar 31.8mm(1.25inch) / 26mm(1.02inch) / 25.4mm(1inch) The bicycle rest handle is very light and easy to adjust and install. You can adjust the armrest length at will, so that you can get rid of the arm and hand numbness on the bicycle and ride for a long time without being tired. Suitable for road Bikes, mountain bikes, triathlon, long-distance travel bikes, etc.