Hold back (back stop) devices manufactured by NMT & Associates are normally used as overrunning clutches, where the shaft overruns at .high speed

These units have individually spring loaded centrifugally lift off sprags, housed in a cage by means of pins connected with rotating inner ring having driving contact with outer ring, and bore dia up to 220 mm. Application:  in inclined conveyors,  elevators, pumps, blowers, fans, gearboxes, , geared motors, pumps and compressors, ball mills, starter.