Function: 1.Made of premium brass and rubber material, sturdy and not deformed, can stand the test of time. 2. Wellnut uses M5 x0.8mm bolt inner diameter and 5mm / 0.2in outer diameter. 3. Direct replacement of the original standard, old or broken one. 4.Suitable for most windshield, body and other motorcycle and ATV applications. 5.Convenient accessory for blocking holes and blocking vibrations