Wooden clock 3D puzzle building kit with mechanical gear and spring wind-up system Pop the laser cut pieces out from the wood sheets and slot them together for a glue-free assembly Wind-up spring allows the gears to move and keep the time for roughly 5 hours on a full wind-up Beautifully engineered to delight hobbyist as well as perfect example for educating teens on physics Perfect for birthdays, stocking stuffers, party favors and holiday gifts for kids and even adults! ROKR is a DIY wooden 3D puzzle craft kit featuring mechanical gear system. The package includes a set of wood sheets with precisely laser cut pieces that assemble together to form the pendulum clock It also includes a spring wind-up mechanism that integrates with the wooden gears allowing the assembled clock to tick its time for roughly 5 hours with a full wind. The item has been designed to target wide range of audience - ranging from hobbyists and puzzle builders to teens and adults who just loves making things! It can also become a great bonding project with smaller kids as a helper to find the right parts and teach them with how gears work. There are no scissors or any other tool required for assembly as all the parts fit together and lock themselves in without any glue. ROKR Pendulum Clock is a perfect gift to bring and steal the attention on birthdays and as stocking stuffers to delight everyone with a kid inside their heart!