Works as a gray card for setting critical white balance. Can also be used as an exposure and focusing aid for close up or macro photography. The thick edge (about 3/8") keeps it very stiff when open. The case measure about 5" in diameter when closed. Due to the thick edge, it is about A... Works as a gray card for setting critical white balance. Can also be used as an exposure and focusing aid for close up or macro photography. The thick edge (about 3/8") keeps it very stiff when open. The case measure about 5" in diameter when closed. Due to the thick edge, it is about 1" thick when folded into the case. A bit bulky. Easy to fold. Simply grasp by opposite corners and twist your hands in opposite directions. Case has a loop to hang on your belt or bag strap, if you want to go for the serious photo geek look. What's not to like? Read more

Very sturdy. Great price. Perfect size to carry around and check for white balance. the other side is white and can makeshift as a small reflector for light. Very sturdy. Once taken out from the bag, it is very difficult to squeeze it back. I am afraid I might break it soon just because of the to... Very sturdy. Great price. Perfect size to carry around and check for white balance. the other side is white and can makeshift as a small reflector for light. Very sturdy. Once taken out from the bag, it is very difficult to squeeze it back. I am afraid I might break it soon just because of the force that's needed to twist it back to a small circle to fit into the bag I still think this is a good buy, even if I just keep it in the expanded state. Small enough to carry around too. Will recommend to friends. A must have for photographers. Read more