The Zeiss Standard RA was the first gray Standard microscope that Zeiss produced in the 1960s. This type of microscope can still be found in many laboratories along with the other gray Standard models. The RA is more compact than its successors and the adjustment ring for the field diaphragm is still made out of metal. I use this microscope with both achromats and Neofluar objectives.
Zeiss Standard RA with phase contrast condenser, magnification changer and nosepiece for 5 objectives.