This sale is for one Mamiya RB/RZ67 WLF -3 Dioptre for the standard RB ProS/ProSD and RZ waist level finders. It will not fit the original RB67 Pro finder – the one without the catch on the sliding locking bar.
This dioptre simply clips into the WLF. This dioptre is boxed (although the box is a bit tatty), and has minimal signs of use. The glass is perfect. Very hard to find.