This is the Idler Gear for the Transmission on the Custom Works Enforcer GBX Kit. FEATURES: Nylon Construction Direct Replacement part INCLUDES: One molded idler gear REQUIRES: Idler Gear Shaft (CSWC4355) Two 3/16x3/8" bearings (CSWC1226) Istallation into the Transmission SPECS: Gear outer diameter: 0.63" (16mm) Custom WorksPart CSW4354