Very interesting! I haven't come across these before. Being able to cut notches for any format is a great feature! What length of film can these hold?
A normal 220 length. 116 and 616 lengths fit comfortably in the reel.
Notches must be accurate. I file a little at a time, checking with film as I go.
So far I've filed extra notches for APS and 70mm.

