The Adapt-A-Roll 620 holder is a roll holder that slips in like a cut film holders, and is similar in concept to Calumet's C2 holder. The film chamber, which holds feed and take-up spools, is at one end of the device. When the holder is inserted into the camera, the film chamber protrudes from the right (viewed from behind) side of the camera. They appeal because they make it possible to use 120 film with press and view cameras that have spring backs.
As its name indicates, the Adapt-A-Roll 620 was designed for 620 film. It can feed film from a 120 spool, but will take up only on a 620 spool. A 120 spool won't fit in the take up chamber, and the wind mechanism won't engage a 120 spool. Taking up on a trimmed 120 spool will not work either.
If this seems like too much trouble to you, Film for Classics sells respooled 120 film on 620 spools.
In spite of having to respool film after exposure to preserve my stock of 620 spools, some people find the Adapt-A-Roll 620 preferable to the Graflex 6x9 roll holders because it has a larger gate, 58 mm x 84 mm. The Graflex 6x9 roll holders have a 58 mm x 78 mm gate, and really are 2 1/4 x 3 1/8 as Graflex, and no one else, claims.
The Graflex holders have three advantages over the Adapt-A- Roll. Easier loading, safer film advance, and easy-to-find instructions. [And perhaps a fourth: some readers report that the Adapt-a-Roll interferes with the focal plane shutter on a Speed Graphic.] It isn't at all clear how to start film in an Adapt-A-Roll, and there's no obvious mark to align any of the arrows on the film's backing with. The Adapt-A-Roll doesn't stop automatically after advancing one frame, the the Graflex holders do. As none of the usual sources for manuals has been able to provide one for an Adapt-A- Roll, I've had to figure out how to load mine by trial and error.
What works for some is the following: thread the 120 film paper backing through the holder and to the takeup spool, close the holder, and advance the backing until the adhesive tape at the head of the film just enters the gate. Then insert the dark slide, set the frame counter to the black outer S mark, advance the film one and one quarter frame (5 clicks, until the inner red scale indicates 1), and the holder is ready for shooting. In practice, the 6x9 Adapt-A-Roll gives 9 shots from a roll of 120 film.
I've seen a handful of 2x3 and 4x5 Adapt-A-Roll 620 holders in flea markets and advertised in Shutterbug. They also turn up occasionally at photo fairs. [Also, see the list of commercial web sites in the Where to Get One page.]
I have two 6x9 Adapt-A-Roll holders, S/N 9670 made by the L. Tatro company of Culver City, CA and S/N 16211 made by TA-MAR Inc, also of Carson City. The two are identical in all but two respects, maker's name and the type of leather used to cover the film chamber. When I got 9670 it had, like most of the Adapt-A-Rolls I've seen, a frame counter that didn't work. Applying graphite powder or Molykote to all moving parts and working them fixed it.
Some Adapt-a-Roll type holders wind the film emulsion side in, while others wind it emulsion side out. Emulsion out is a nuisance, since the glued paper strips for sealing up the roll assume it will be wound emulsion in.
Thinking of unlikely 'Graflex' roll holders, I have a lever advance "Graflex/Subsea" 2x3 RH8, S/N 0384-1087. It was made by Subsea, who bought the RH tooling from Singer when Graflex was closed and seem to have sunk without a trace. I bought it as new and unused. When I first used it, it was so problematic that I'm convinced it really was unused. The box said RH8, the outer casing had a 6x9 gate, and the frame counter went to 8. In spite of all this, the film carrier spaced frames too close to be usable in a 6x9 casing. Not only that, it jammed intermittently. Armato Camera, 67-16 Myrtle Ave., Glendale, NY 11385 overhauled it for me. They reported that it had been assembled with a frame-spacing cam for 6x7, and put in the right 6x9 one. Since then the thing has been ok, but has seen only light use.