Easy to print puzzle which I created from an aluminum copy that I purchased a few years ago. I printed this copy at .75 scale but the file is for the original size of the aluminum puzzle (60 mm, 60 mm, 40 mm). The puzzle, even at 3/4 scale, slides easily and works well. After printing the hardest part is putting it together correctly. There are a few ways to get all of the keys ("pistons") into the house but when put together correctly only one piston should be able to move. Print the keys flat as is. To print the "house" rotate on one side to minimize supports. I printed this copy at .2 mm layer height, 30% infill, 3 solid layers on top and bottom, and supports enabled.