Simple Clock Mainspring Winder a Bergeon quality Swiss made mainspring winder, simple execution. This winder has a pawl that allows the user to wind mainsprings in either direction. Length of frame is 105mm, includes 3 hooked attachments and 1 double pin. Simple Clock Mainspring Winder adjusts vertically for holding the mainspring. Simple Clock Mainspring Winder is designed to be held in a bench vice.