For the count -[ HMM ]-

One gang (section) of a two-gang 35mm film synchronizer. These devices, which also came in 16mm, 70mm, and 16mm/35mm versions, were a common tool back when film was edited by hand.

 

The sprocketed wheel measures sixteen frames (one foot — 304.8mm — of film) for each revolution and is marked so that the film can be laid in frame. The unit also has a mechanical counter off to the side for footage measurement.

 

Once a staple of the editing suite, I now use this device in the projection booth for film measurement and a frame finder.

Done