This is a vintage Cibachrome 8x10 Color Processing drum. These are great to for regular photo B&W or color paper processing. This can be a good solution if you don’t like tray processing, are working with minimal darkroom space, or just prefer daylight processing tanks.

The lid to the tank has a small reservoir to hold developer and other chemicals. It holds about 250ml. This means the tank can be filled with this much developer while upright and the chemicals do not reach the film. Once you are ready to start developing you lay the tube on its side on a flat surface and the chemicals now fill the main body of the the tube. You now need to roll the tube back and forth on the flat surface for the entire development time.