Cassettes/Freewheels

The product that set the standard and still the best available! The GC line of cassette extender cogs allow you to modify your 10 speed cassette into a wide range cassette. To achieve the optimal shifting, the GCs are optimized for Shimano or SRAM cassette -- always select the correct type for the brand of cassette you have. Compatibility: - Compatible with Shimano 10 speed cassettes listed on the GC tech page - Compatible with all 10 speed chains - Note that you may need a longer chain that you currently have on your bike - Chain stretch should be less than .5 when installing a new GC - Compatible with all 10 speed rear derailleurs except non-clutch type SRAM rear derailleurs model year 2012 and older - Can be run in 2x configuration with a long cage rear derailleur

Light, strong with extra tall teeth, the Wolf Tooth Aluminum Single Speed Cog is a lightweight option for single speed cogs that's offered in a variety of sizes. - Wide 4.5mm base won't dig into your freehub - Made of 7075 Aluminum Alloy for durability and lightness - Made in the USA

Designed to be an extra durable single speed cog option, the Stainless Steel cog features extra tall teeth and a wide 4.5 mm base to limit freehub gouging. - Made from hardened and electropolished 416 stainless steel compatible with 9,10,11 speed chains