Chain and sprocket are widely used in many engineer projects.It is matched to use,so some customers will purchase the chain and sprocket together some times.Follow picture are SS50-K1-6L chain and SS50-1-20Z sprcokets matched projects.SS40-DD3-K2/8L chain and SS40-2-28Z sprocket matched projects.C2080H chain and C2080H-18T,C2080H-13T sprocket projects.