Gears and motion
The standard 3D-printer stepper: 42.3 mm square, 31 mm M3 hole pattern, ⌀22 pilot and ⌀5 D-shaft. Body lengths 34, 40 and 48 mm.
Solid Vibes StandardGears and motion
The tiny geared 5 V stepper from ULN2003 kits: ⌀28 can, 35 mm ears and an offset ⌀5 flatted shaft.
Solid Vibes Standard