Professional version of the #451 4-S Light Reducer. A Neutral Density (ND) filter that cuts the light by 4-stops, changing the effective speed of Type 47 3000 ASA picture roll to 200ASA, permitting its use outdoors. Push fit on the 46mm lens flange of Model 110A, 110B and 120 lenses — it does not fit the 110 without an adaptor. Early American production with thick glass (top right), Japanese (top left) — note rotation of logo, letter spacing and condensed font.

Late Japanese manufacture box and keeper — keeper has moulded Made in Japan on base