All our motors are standard NEMA 56 frames and fit over 90% of the woodworking machinery on the market. If you have applications where dust, oil, chips or other foreign particles are the norm rather than the exception, you should use these Totally Enclosed Fan Cooled Motors (Enclosed). Motors are dual voltage (110/220V) capacitor start. They feature standard NEMA 56 frames, all ball bearing construction, reversible rotation, 5/8″ shafts, and are rated for continuous duty. Not for air compressor use.