This sale is for a brand new in box Mamiya 645 Eye Correction Lens -1.5 D for the Super/Pro/ProTL and M645 waist level finder (WLF). I have other dioptres available, and if you cannot see what you want just ask.
This dioptre simply replaces the bayonet-fot dioptre in your WLF. This dioptre is new although the storage box is not in great condition. This dioptre fits both the older M645 WLF and the newer Super/Pro model. It is the standard dioptre supplied with these WLF when new; if you have bought a WLF with a non-standard dioptre and you are having problems with focusing then this is probably what you need.
A large (but definitely nowhere near complete) selection of Mamiya, Bronica and Fuji GX680 dioptres available and I do not have time to list them all; if you cannot see the one you want then just ask.