With this replacement cog, you just need to change the outworn one rather than the whole cassette, and please sure the teeth and speed of your cassette to fit the cog before order.
Feature:
High duty steel construction, strong and wear resistant.
Designed for shifting performance.
For road bike and mountain bike.
Specification:
Material: Stainless steel
Teeth: 11T / 13T (optional)
Speed: 8S / 9S / 10S / 11S (optional)
Package weight: 12-21g / 0.4-0.7oz
Package list:
1 *Bike Cassette Cog