This is a winder specifically for the CONTAX 159MM body. I am selling this without the body, so I haven't been able to perform a practical test, but it did operate using the test button. It's in very good condition and doesn't show its age. It uses six AA batteries, which the buyer will need to provide. Thank you. - Model Name: CONTAX 159 WINDER W-7 - Color: Black - Test Function: With test button - Compatibility: For CONTAX cameras - Design Features: With grip Thank you for looking.