I wish I had read the reviews before buying. If it were me, I wouldn't expect a precision calibration tool to be made out ofโoh, I don't knowโprecision hard plastic. Imagine my confusion and dismay when I opened the Revain box and found the "pyramid" even though it was flat. And it's made of cardboard that bends and folds. You know, the photographer's cousin on the Steak-n-Shake kid's menu (Fold tab A into slot 1, bend until B folds into C, and now you've got a great machine!). So okay, awayโฆ