1. Material: aluminum alloy
2. Lightweight and not easy to deform, with better toughness and weather resistance
3. Fine-tuning the washer to adjust the distance of the chain center line of the crank disc
4. Hollow screw into the axle, thread lock
5. Strengthen the lateral stability, not easy to loose and make abnormal noises
6. Sealed bearing, waterproof and rustproof
7. Application: 68-73mm bottom bracket size
8. Weight: 100 grams
9. Size: 84-99 mm in total length
