Product major function & usage:
Pad below the screw head to prevent the screw twisting too hard and crushing the parts or accesssories.
Major advantages of upgrading to this product:
Stainless steel is an impact-resistant, wear-resistant material and it is not easy to rust
Other special notes and comments:
1. Inner diameter : 4mm
2. Inner thickness : 1mm
3. Outer diameter : 10mm