Rennen Aluminum Cassette Cog Gear Size:17T plus plastic bumpers under the

plus plastic bumpers under the nose and tail to help protect against wear

React faster out of the gate with the FASTR REACT

Full chromoly and heat treatment make these cranks the perfect replacement or upgrade crankset for kids with low dough

S-Spec tires conform better to track surfaces for buttery smooth runs

BEARINGS: Japanese sealed bearings throughout

Rennen Aluminum Cassette Cog Gear Size:17T plus plastic bumpers under theRennen Aluminum Cassette Cog are manufactured with 7075 T6 Aluminum, stronger than the industry usual of 6061 Aluminum. Measuring in at only 3 16" so it won't rub your hubs, Rennen Cogs are also the one of the lightest cogs on the market, with the 16T coming in at only 17 grams! Available in a wide range of sizes for various speeds, Rennen Cogs are also Shimano Spline compatible and will work with 8 & 9 speed chains. WEIGHT 13T: 0. 35oz 10g 14T: 0.