The units are made of 3mm plywood and the pieces are individually slotted to interlock with one another to form a 3D model. Everything is pre-cut and assembled by pushing the pieces together. There is nothing to cut or glue. HIGHLIGHTS: - Kits are made of 3mm ply-wooden board. - They are delivery in flat packed board, shrink wrapped. - All pieces interlock with each other forming a 3D model. - NO cutting tools or glue required since all designs arepre-cut. - Items can be painted, stained, or glued together, but not necessary.