| Size (in.) (mm) | NEMA motor mounting size | ||||||
| NEMA 8 | NEMA 11 | NEMA 14 | NEMA 17 | NEMA 23 | NEMA 34 | NEMA 42 | |
| Motor size (DD) | ~0.8 (20.32) | ~1.1 (27.9) | ~1.4 (35.6) | ~1.7 (43.2) | ~2.3 (58.4) | 3.4 (86.4) | ~4.2 (106.7) |
| a: Bolt hole distance (square) | 0.630 (16) | 0.905 (23) | 1.024 (26) | 1.220 (31) | 1.854 (47.14) | 2.744 (69.7) | 3.500 (88.9) |
| b: Motor shaft diameter | 0.157 (4) | 0.197 (5) | 0.197 (5) | 0.197 (5) | 0.250 (6.35) | 0.375 (9.5) | 0.625 (16) |
| C: Motor shaft length (Max.) | 0.945 | 0.81 | 1.25 | 1.38 | |||
| d: Guide diameter | 0.590 (15) | 0.866 (22) | 0.866 (22) | 0.866 (22) | 1.500 (38.1) | 2.875 (73) | 2.186 |
| e: Pilot depth (maximum) | 0.059 (1.5) | 0.079 (2) | 0.079 (2) | 0.079 (2) | 0.062 (1.6) | 0.062 (1.6) | 0.062 (1.6) |
| f: Bolt hole diameter | 0.891 (22.6) | 1.280 (32.5) | 1448 (36.8) | 1.725 | 2.625 | 3.875 | 4. .950 |
| g: Bolt hole dimension | 0.118 (3) | 0.157 (4) | 0.157 (4) | 4-40 UNC | 0.195 (5) | 0.218 (5.5) | 0.281 |
