NATIONAL GEOGRAPHIC Hobby Rock Tumbler Kit - Rock Polisher for Kids & Adults, Durable Noise-Reduced Barrel, Rocks, Grit & New GemFoam for a Shiny Finish, Cool Toys, Great STEM Hobby KitCREATE YOUR OWN GEMSTONES Rock tumbling is a hugely popular hobby for kids and adults! This robust rock tumbler makes it fun and easy to turn rough rocks into beautifully polished gemstones, thanks to its simple operation and durable design. A TUMBLER THAT'S MADE TO LAST The durable motor has tumbling time control settings so you can set it and forget it. The leak proof barrel features a stainless steel lid and is 75% quieter overall than plastic