Stackable cover for IKEA SOCKERBIT

My wife only allowed this IKEA SOCKERBIT for my little workshop in the apartment. But this sice don't have a lid so they can stack. Made this slide-on cove as a prototyp. Still working on a much better shape for more strenght, less print time and material consumption. It works fine, if someome has the same problem. The SOCKERBIT size is 19x26x15 cm