Shimano TZ510 6 Speed Freewheel Shimano 6sp MTB system Improved corrosion resistance for outstanding durability Teeth: 14-28T Speeds: 6sp 14-28T Specifications: Cassette Body Type: Freewheel Cassette Cogs: 14-16-18-21-24-28 Drivetrain Speeds: 6 Color: Silver/Black