Number of Teeth (Chordal Action)Nom. Pitch DiameterNom. Outer Diameter Nom. Hub Width Available Bore Sizes
inmminmminmmRound inSquare inRound mmSquare mm
18 (1.52%)5.71455.81482.051 1.5, 2.5 40, 60
21 (1.12%)6.71706.81722.051 1.5, 2.5 40, 60
31 (0.51%)9.925110.12572.051 3.5