Small component inserts for Really Useful Boxes scrapbook drawers

Inserts to fit into the Really Useful Boxes scrapbook drawers hobby trays, giving more options for storing smaller quantities of small parts, for example, LEGO. These fit exactly into one compartment, sub-dividing them into two, three or four smaller compartments. I've also provided two heights, 40mm and 60mm, because it can be tricky getting fingers into the bottom of the taller 3- and 4- compartment ones. The boxes have a two layer base and 0.5mm walls to minimise weight. Print profiles are 0.28mm layer height for quick printing.