A packing puzzle. Insert the pieces into a 3x3x3 box with a special handle.
This is a difficult puzzle with 31 moves needed to solve it. Difficulty 188.8.131.52.
I recommend printing this and the basket in the larger format.
Check out the other similar puzzles in the series. You shouldn't attempt this puzzle as your first in the series. I haven't included the basket files in this posting, you must download and print a basket from one of the earlier entries: https://www.thingiverse.com/akaki/collections/akakis-picnic-basket-packing-puzzle-series
Inspired by Mushroom Basket by Andrey Ustjuzhanin: https://www.thingiverse.com/thing:4726487
The "large" size is compatible with the wooden baskets from CubicDissection and my Etsy shop.