The third generation (1977-on) had the designation MD, with the third variant (referred to by Minolta as 'New MD', 1981-84) being the last series of MD lenses manufactured in-house by Minolta. This listed lens is a New MD lens, and note that in common with all new MD lenses it features a minimum aperture lock (in this case at f22) to accomodate the proper use of features on the XD-7 and X-700 SLRs which required the lens to be set at minimum aperture.
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