Keep It Shut!

Warding off any wrong attempt to pack the four pieces in the box and close it will have Keep It Shut! disapprovingly re-open it's lid automatically as a way to show the packing is rejected.
The higher goal is to pack and move the pieces in the box so that the lid remains shut.
In the inner space of 3x3x3, many different packings (around 6K) are possible, however there is only one solution.
In difficulty we give this puzzle with a mind of it's own four stars.

The mechanism

Get Keep It Shut! here: Order your customized puzzle locally printed via the Treatstock hub.

Get the STL's here: Order the STL's for DIY 3D print via Paypal and receive the files by email.

price/$13.24

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