The concept of mechanical puzzles has been around quite a long time, and the team at Craighill is keeping the tradition going strong with their collection of beautiful interlocking puzzles, one of which is known simply as “Tetra”.

This is one of those puzzles that seems simple enough on the surface — there are only four pieces to assemble, after all — but the solution difficulty can be easy to underestimate:

Once assembled, you'll have an attention-grabbing little tetrahedron sculpture that looks great on your desk and can be played with again in the future whenever you need to get your gears turning.

Get the Tetra puzzle for $98 on Amazon in your choice of Brushed Stainless Steel or the PVD-coated Vapor Black.