Precision Tork™ units provide constant torque independent of slip speed. They offer excellent overload and jam protection for all drive train components and also provide soft starts with zero slip when a preset torque is reached. This unit (MB5.5-1) features a bore size of 1 in, a 1 to 45 in-lb torque range and a Max speed of 1800 RPM. Warner Electric® Precision Tork™ Permanent Magnet Brake, Standard Type MB5.5, Series: MB Series, 1 in Bore Dia, 5.29 in Outside Dia, 4.53 in Overall Length, 1 to 45 in-oz, 1800 RPM Maximum, Rear Mount, Stainless Steel