Eclair 35mm Cameflex Gearbox Rotary switch unit for shutter open/closed for movie camera. Communicates to external equipment when the shutter is open and closed. Used often in conjunction with an intervalometer for time-lapse or for triggering lights etc etc. Included are three new-old stock connectors which mount on to the units vintage 3-pin connectors. Unit attaches to the right side of your camera's aperture plate (you slide up the two movable covers). will work with Standard and CM3 models.
I have many other related items, please check my listings.