Specifications Rear sprocket: 34T/ 35T/ 36T/ 37T/ 38T/ 39T/ 40T/ 41T/ 42T/ 43T/ 44T/ 445T etc. Front sprocket: 13T/ 14T/ 15T/ 16T/ 17T etc 415, 420, 428, 428H, 520 etc ....