This handy dandy half link from KMC allows for precise chain length adjustment for 1/8" track style or 3/32" standard chains. Great for those seeking a precise wheel alignment on a fixed gear, perfect brake pad location for an urban fixed gear and riders looking for the perfect chain length on stadard drivetrains. Steel construction is bomber and installation is a snap. Choose size: 1/8" fits most 1/8" chains while the 3/32" fits most standard 9.4mm width chains.