USE WHITE FILAMENT ONLY FOR IT TO WORK!!!!!!! hold it up to light and watch the magic happen!! printed on anycubic vyper, not predator. vyper wasn't an option for some reason. If you enjoy this model, check out itslitho.com to make your own custom lithophane for free! If you liked this also please follow me and like this model. I am new to 3-D printing and 3-D modeling.