Renthal 520 Twinring Heavy Duty Rear Sprocket Black - 51T - 1540-520-51GPBK

Features:

• Unique flat face design keeps weight to a minimum and means the TwinRing is as narrow as a regular chainwheel
• Inner Ring is high strength Ultralight 7075 T6 Aluminum. Outer Ring is Electroless Nickel Coated steel
• Outer is expanded at 200C and then fitted to inner, creating a permanent bond for the life of the sprocket
• Precision CNC machined to extremely tight tolerances
• Flat socket head screws add additional strength to the chainwheel during side impacts
• Self-cleaning mud grooves between every tooth on both sides help prevent dirt build up