The Westcott Optical Spot by Lindsay Adler Creative Color Gel pack is an add-on accessory for the Westcott Optical Spot. This gel pack can be used with most flash heads up to 100W to project vibrant colors on any surface. Colors include Magenta, Daylight Blue, Teal, Violet, Straw, Blue Green, Lavender, Light Flame, Light Purple, and Moss Green.