This Standard contains the following information for Flexible Chain Couplings: is One member of a broad family of mechanical shaft connectors that transmit torque without slip and that will accommodate a moderate misalignment between axially oriented driving and driven machine members. This Standard covers couplings of the chain type where two hubs having chain sprocket teeth are engaged by means of a length of roller chain or silent chain. The main topics are (a) General dimensions; (b) Misalignment capabilities; (c) Covers; and (d) Lubrication. Tables are also provided for (a) Single and double roller chain types; and (b) Silent chain type.