Gehmann #50309 Add-on 1.5 Diopter only -4.5 to +4.5 Diopter (for Gehmann only)

50309 1.5x diopter only
This diopter is meant to retro fit on Gehmann iris only.

1.5x magnification with -4.5 to +4.5 diopter correction
Retro-fittable to all our Gehmann irises with detacheable thread only
Identifiable by the back-plate which receives the narrow body-lock key for detachment 
Either diopter is then simply locked to the iris body and used as before
Include adaptor #577