NEMA 56 frame capacitor-start/run general purpose AC motors have a standard 5/8" diameter, 1-7/8" length shaft whose center is 3-1/2 above the base mounting surface. Variations to the frame's standard dimensions and design are indicated by a letter designation following the frame number, such as 56HZ or 56C. The letter "H" indicates that the frame has a set of mounting holes at 3" and 5", "Z" indicates that the frame has a nonstandard shaft, and "C" indicates that the motor can be face mounted.