These couplings have simpler designs that sandwich a rubber buffer (nitrile rubber) between two hubs. The hub is lightweight, being product of aluminum alloy. The uncomplicated construction sandwiches a spider (rubber buffer) between hubs, so the coupling is definitely mounted or removed via transferring the system within the axial direction. Mounting on a shaft is easy. Simply maintain a straight-edge to the hub periphery to center it.One source of attraction is that its uncomplicated construction skill lower cost. Application Pumps/Fans/Textile machinery