Features:Includes 3 colour calibrated reference cards supports you get appropriate white balance, or coloration balance, allowing the camera to make amends for the illuminant coloration in a scene optimum colour correction: the black card achieves really deep blacks (RGB 16,16,15); the gray card displays advanced spectral neutrality with measured values of 162, 162, 160; the white card has a tested RGB value of (220, 224, 223) neck strap with quick-release plastic buckle at the end, convenient for your use Specifications:Item size: 85 * 54mm / 3 * 2: Black/White/GreyPackage weight: 34g / 1 Package List:3 * Balance Cards1 * Neck Strap