The Cameron 20" Color Balance Coach Disc looks like a collapsible reflector, but it's actually a large gray card that will still fit in your camera bag--it has 4 patches that can be used for color balancing your photographs. The 18% gray patch is made of chromatically neutral material that will remain stable for many years. The black patch reflects only 3% of the light striking it. The white patch reflects more than 92% of the light. The dull translucent patch reflects 80% of the light and will allow a shoot-through white balancing area and a reflected low-light reflected white balance patch. Carrying bag is included.