Jaw Coupling Hub; 4" Hub Dia; Jaw Coupling; Hub; Shaft; Spline; No Keyway; 4.5" Outside Diameter; 1.94" Length Thru Bore; L190 Size or Series; Clamp; Sintered Iron; 5000 Maximum Speed; NBR 1728 | Hytrel/Bronze 4680 | Urethane 2592In-Lbs Torque