These are color conversion filters for the use of daylight type color films with artificial light source. 80A increases the color temperature from 3200°K to 5500°K for the use with 3200°K lamps. 80B increases the color temperature from 3400°K to 5500°K for the use of photoflood lamps. 80C increases the color temperature from 3800°K to 5500°K for the use of clear flash bulbs.

This is the Extra Quality, Mulit-Coated version of the 80A filter.