UGEARS Book of Secrets 3D Wooden Puzzles for Adults - Mechanical 3D Puzzle Model Kit - Brain Teaser Puzzles for Adults, DIY Adult Craft Model Building Kits, Wood Puzzle Box, Gift Hobby Set

Looks good. Had fun building it. And everything functions properly

Very pleased with end result. Take your time, focus on the details and have fun!

This is one of the finest artifacts of human ingenuity that I have ever had the pleasure of experiencing. Not only is this stupendously clever in its design, great fun to assemble, and also extremely well engineered (especially given it is made out of wood!)... but it is also a wonderfully entertaining and genuinely useful keepsake for a child to keep their secret things safe :)

I've put together more than 100 3D wooden mechanical puzzles including book nooks and I have to say, this is one of my favorites when completed. There are some really fragile pieces so make sure to "take your time & pay attention" to the details. If you do that, you will have no issues. I recommend this one and would definitely buy it again.

I very much enjoy putting together mechanical puzzles, and this one did not disappoint. The instructions were easy to follow, the pieces are well made, and the finished "book" feels sturdy in hand, could hold a couple small items, and serves well as a piece of decor.

It worked as it should

I genuinely wanted to love this puzzle, but after 10 painstaking hours, I had to give up—and not because of lack of effort or skill. The core issue is poor design and tolerances. Many of the pieces are extremely difficult to fit together, requiring far more force than should ever be necessary for thin wooden components. As a result, multiple pieces broke during normal assembly, despite following the instructions carefully and working slowly. Several parts simply do not seat correctly, making later steps impossible even if earlier steps are done exactly as instructed. This isn’t a matter of challenge or complexity—it’s a manufacturing and design flaw. A mechanical puzzle should be precise; instead, this feels unforgiving and fragile, where one tight fit or misalignment ruins hours of work. Once a piece breaks, the entire build is compromised. For the time, cost, and frustration involved, this was a major disappointment. I do not recommend this product unless you’re prepared for broken parts and an unfinished build.

This is a fun little kit. It's a great way to spend a couple of enjoyable evenings. The finished kit is very nice and works quite well. It is decorative, not an actual "safe". But makes a nice conversation piece on the bookshelf or coffee table.