Stackable Puzzle Piece Organizer Tray (thicker)

This is an optimized version of @Panacaguy's very nice trays for use when not using solid infill layers. These have a 2mm base layer to make an sparse-infill-only base a bit stronger. I find that a sparse-infill like gyroid gives both a nice effect and is a great base for sieve-filtering dust from brand new puzzle pieces.