CameraTrax 24ColorCard-Set-3 with 12% White Balance Card and User Guidebook Set of 3 standard (2x3, 4x6 plus 3x4) 24ColorCards, each with GreyCard and convenient protective sleeve Precision 12%-Grey reference for white balance plus 24-Color patches with RGB values for superior digital color correction Double-sided construction, archival quality acid-free materials and color printed User's Guide Detailed instructions included for Picasa 3.8, Photoshop Lightroom 3, Photoshop Elements 9.0 and Photoshop CS4 This is the Set-3 option of the CameraTrax 24ColorCard family: 2x3, 4x6, Set-3 and the NEW 24ColorCard-3x5 (OneSnapColor) !