Serial# 2380000- 2385034 from 1961-65. About 5035 made. Meter could be installed. 75mm Xenotar 3.5, Planar 75/3.5 or Opton 75/3.5 lens. EVS system. Detachable hood. Bay II. Distance between lenses expanded from 42mm to 45mm. The Xenotar lenses were changed to 6 elements starting with lens serial# 2753002, self timer.