This is an insert I designed to fit my Dewalt 2500 Jumper box. I printed this out of Tough Pla and mounted it in the box of my truck. It has sat back there under a tonneau cover for the past year and has kept its shape and has done what it is supposed to do. I might consider printing it in PETG or ABS, ASA if you do not have a tonneau cover. I have included the STEP file if you would like to make any changes to it.