Following M23 connector can be used in servo motor:
Power Male 90° Flange-Mount 4x Ø 2,7 mm,rotatable,Flange 25x25 mm
Power Male 90° Flange-Mount 4x Ø 3,2 mm,rotatable,Flange 28x28 mm
Power Male Flange-Mount 4x Ø 3,2 mm