• It is made of high tensile Steel and made by the technology of quench-temper hardening.so it has higher strength, durability and has extreme resistance to abrasion. The strong antioxidation makes it hard to rust to have a long service life
• High precision teeth ensure close connection with bicycle hub for smooth rotation and easy maintenance
• The hollow design reduces weight and makes your riding easier
• Use it to directly replace your old or broken flywheel. A wonderful accessory for most mountain bikes. Easy to install

Specification:

• Speed: 11 speed
• Material: Steel
• Teeth rate: 11-13-15-17-19-21-23-25-28-32-36T