ROKR 3D Wooden Puzzle-Mechanical Model-Wooden Craft Kit-DIY Assembly Toy-Mechanical Gears Set-Brain Teaser Games-Best Gifts for Adults & Teens Age 14+(LG504-Tower Coaster)

This kit is amazing! Pieces are precisely cut, easily marked with part number, fit together well. Instructions are pictorial and sometimes need to be figured out. Works like a charm!We put it together as a family a family which took an afternoon. Not recommended for small children. Can't wait to do another.

I started with a smaller a ROKR model and loved it so much I bought another. It was fun to build and see how the parts fit together. The footprint if the model is smaller a piece of paper so it doesn’t take up a lot of space on display. There are some points where marble gets stuck( at the directional arrows). But it is still a great model. I bought another one to build as they make 4 different runs.

Excellent - instructions clear and concise and all parts fitted perfectly. Final product providing much enjoyment

It was a good challenge. Arrived on time and in good condition as described. Needs delicate handling and concentration but it was a rewarding building experience. Very well designed and by following the instructions you end up with a nice little working toy. Looks impressive as well. Well worth it.

Quick Summary: Terrific sturdy contraption that is a feast for the eyes. Build will be lengthy but with patience comes its just rewards.I'm a big fan of building contraptions and having gadgets that you can see work before your eyes. This ROKR 3D Wooden Puzzle-Mechanical Model-Wooden Craft Kit is a perfect contraption for kids and adults to own and enjoy watching. It's completely hand driven (no batteries) so if built correctly, you'll be able to watch this contraption run as long as you're cranking the winch. The entire build is made with wood and the material is sturdy, and it measures approximately 8"x9" give or take.During the build process, I unfortunately broke one part but it was a tiny piece the size of a grain of rice and luckily they have plenty of spares; probably assuming users might break this part a lot so better to have extras than only one piece. The build did take a LONG time and it does get pretty tedious with the tiny parts, especially when inserting many tiny pieces in. They provide all the material you need and you don't need any of your own tools to help build this. They also provide some wax as a lubricant in some of the gear pieces so it can run smooth as well as a piece of sandpaper to carefully wipe away any splinters, so that's useful. Your nails will get a bit sore overall but once you have it all complete, it is totally worth it.Once it was complete, running the contraption was a piece of cake and enjoyable to watch the balls run continuously over and over. Depending on how you build, you might notice sometime that the ball stops but just adjust the piece that is not positioned correct and it'll fix the issue no problem. Running it for a couple minutes had no issues with anything breaking and is a perfect eye catcher for visitors. An interesting thing about this contraption is there's actually multiple routes the balls can go so every time a ball passes through, it'll change every time.If you're a fan of building and even Rube Goldberg-like contraptions, this gift is a perfect gift for you or your family builder.