Rondinax Winder coupler - 51.6mm version

This coupler is intended to fit over Rondinax drive knobs up to 51.6mm in diameter. Probably minimum diameter should be approx 51.3mm. If less than that the coupler might be too loose. Measure your Rondinax unit carefully. A small sample of measured Rondinax knobs suggests that sizes can vary. Customization of the coupler size is possible. The coupler is intended to be driven by a solarbotics GM2 gearmotor. Go to the solarbotics website and check the dimensions of the output of the GM2 gearmotor. The coupler is designed to fit that output shaft shape only. The coupler is attached to the output shaft of the GM2 gearmotor with a small screw and washer (provided by the user).