Get your flex coupling inserts from Grainger to help complete shaft couplings that can protect equipment from misalignment, vibration and shock loads. Each coupling unit consists of two hubs or flanges and one insert, sold separately. Choose from one- and two-piece flexible EPDM rubber, Hytrel or polyurethane inserts. Polyurethane inserts can offer superior chemical, dynamic and weathering properties. Pick up the flex coupling inserts you need at Grainger.