B&W processing doesn't allow a rem-jet backing.
The best you can do it to have a matte black film pressure plate in the camera. Bolex is fine; Aaton and Arri have shiny chrome and may reflect overexposed light back into the emulsion from behind. You can check this by removing the lens, with no film in the camera and looking at the pressure plate while the camera is running.
You will see circular flare around highlights, for example a car headlights at night. This is light penetrating the emulsion and being reflected back off the base back into the emulsion. On certain cameras with shiny chrome on the pressure plate, you will see a pattern on the negative that matches the shiny bars on the pressure plate.
If you keep the exposure to the low end you will avoid this problem except for the circular halo on point highlights.
If your printing lights are from 18 to 22 or so, it is unlikely to pose a problem. The gray base acts as a anti-halo layer.