"81" series are color corrective filters that 'warm' bluish tones. They are available in several strengths (A, B, C & EF) with 'A' being the mildest warming effect.

• Adds healthy tone to skin tones shot in open shade or overcast.
• Reduces excess blue from flash indoors or in daylight flash-fill.
• Warms (balances) sea, sky and high altitude shots.