This sale is for a really good condition Mamiya RB67 ProS No. 2 Checker (Grid) focus screen, suitable for use with all RB67 cameras. It comes complete with original box and instructions.
This screen is generally pretty clean with minimal marks but one small patch of the grid marking has rubbed off, so the price is much lower than normal. The grid pattern is ideal as a compositional aid, ensuring that everything is exactly horizontal or vertical, as required. A really useful screen. Try finding another one – these are almost impossible to find.