1. Material: stainless steel, cold rolled steel 2. Hexagon socket head screw, adjustable length, convenient and easy 3. The chain is thickened and forged, and the connection is stable and not easy to break 4. With adjustable key 5. Ventilation limit, easy and convenient installation 6. Weight: 98 grams 7. Dimensions: 22x50mm, chain length 235mm