Fluo Graduated Filters are full color explosions. Use their saturation everytime you want to contrast the bright tones of your subject. A field of flowers, a bright yellow house, your model in her pink fluo track suit...the list is endless. Each fluo color comes in two grades: #1 mild, +1 stop. #2 strong, +2 stops. Graduated Yellow Fluo 1 (660) & Yellow Fluo 2 (661) Graduated Orange Fluo 1 (662) & Orange Fluo 2 (663) Graduated Red Fluo 1 (664) & Red Fluo 2 (665) Graduated Blue Fluo 1