The Pentax Refconverter M sounds like it does something really fancy, but it's a pretty standard 90-degree magnifying viewfinder. That's good, though! These are useful tools for macro or copystand work, with switchable 1x or 2x magnification. This Refconverter is designed to mount to Pentax M-series cameras, which includes the ME/MX (and many digital SLRs.) It won't fit the K1000. Spotmatic, or their derivatives. In excellent condition, with case and manual.