This B&W 46mm 81B Warming Color Conversion Filter is similar to a Kodak Wratten filter and comparable to the KR-3 (81C) Conversion filter. Like the 81A, it is recommended for color films that have an inherent reddish tone.
This filter is popular as it leads to a very pleasing skin tone in portraits. In addition, the 81B Conversion filter is ideal for compact flash units with color temperatures higher than 6000K.
Note! Whereas the KR series (and the 81 series) of filters creates a feeling of warmth, the KB Series (and the 82 Series) creates a feeling of coolness