Glue a S-03-01-N
with a small drop of superglue to the backside of each of the 40 puzzle pieces and voila! In the blink of an eye, you've got a mini magnetic refrigerator puzzle!
This and other handmade wooden puzzles can be purchased at PMW
The very small puzzes can unfortunately only be purchased in a PMW-Shop but the large puzzles can be purchased online.