I've been using a 1951 Rolleiflex MX-EVS with f3.5. I love the camera! In winter I am mostly a night shooter. I just bought a Rolleiflash and want to get started in flashbulbs. I have a dozen M2B bulbs. I usually shoot HP5. I'm thinking the M2B are GN=80? Second question I have is about the flash units themselves. The flash I have has a plastic reflector and the cord simply attaches. There is a GN/exposure calculator wheel on the back, and the reflector adjusts for wide or narrow angle. It take the flat Eveready 412 battery (I just bought a new one.) I'm thinking this is vintage early 1960s? THere is another Rolleiflash bulb gun that has a reel inside that winds up the sync cord. It looks older. Is this one from the 1950s? What is the main difference from a user's POV? Finally, I read the sync for the M2B bulbs is 1/30s, X position. I read that the M3 bulbs can sync 1/60s to 1/500s, x position. Will I need an adapter to use these? What does it look like?

Kent in SD