The Leicavit M is a fast winder for manual film transport, designed to replace the bottom cover of an analog Leica M-Camera. It enables photographers to take up to two shots per second without needing to move the camera away from their eyes.
To use it, unfold the rewind crank, pull it to the stop, allow it to spring back, and then release the shutter.
The Leicavit M is compatible with the Leica M-A, MP, M6, M7, M6 TTL, M4-P, and M4-2.