Kodak 9x12 holders: spring load, framed. Do they need a film sheath or not?

I have a small set of Kodak 9x12 holders that I just received in the mail. Unlike my others (Voigtlander & Zeiss holders) which are clearly for plates and take film sheaths, these are a little bit ambiguous. There's a spring loaded back that presses up against a frame to hold (film? plates?) in place. There's a fair bit of room when you press the spring plate back, so I'm not sure if this was designed for plates or film. In short; do I need a film sheath for these or will they work as-is? They look like they would secure film in place, but I'm not totally sure how much slop there would be, if the film will be planar and aligned with the focus plane, etc.

Also, they have a bit of a recess in them; you can see in the images how the border of the pressure plate is raised relative to the center.

Images attached.

Perhaps someone else uses these as well.

I have several of these. They don't need a sheath; the spring holds the film in the right place. I think they're intended to be dual-purpose film/plate holders; the spring has enough give to accommodate the thickness of a plate as well.

I've never had a problem with them, but I remember seeing someone say that they found theirs didn't quite sit square in certain cameras. I've used them on Voigtlaender, Nagel, and Kodak AG/Nagel cameras successfully, though.

-NT

Awesome. I was hoping for that. They fit my Avus & Bergheil perfectly so I'm very pleased.

Well, thanks for the advice; I loaded them up and it was by far the most pleasant 9x12 film loading experience to date. The spring loaded frames are really easy to fill with film and seat in the dark. Perhaps even easier than loading standard 4x5 double-sided holders. Downside is these metal holders are heavy!

You got that right Walter -- easy to load and heavy as all get-out.

Here's a copy of the holder envelope. Hope it's readable.