Discover with Dr. Cool PRO Series Rock Tumbler - Turn Rocks into Stunning Gemstones! POLISH ROCKS AT HOME - Discover the fun hobby of rock tumbling and transform rough rocks into beautiful gems with this deluxe rock tumbler COMPLETE ROCK TUMBLING KIT - Includes 1lb of tumbling stones (9 types), polishing grit (4 types), jewelry fastenings, and instructions ULTIMATE TUMBLING MACHINE - Featuring a long-lasting motor, automatic shutoff timer, leak-proof rubber barrel for quieter tumbling, and speed control settings START A ROCK COLLECTION - Spark a child's love of geology and learning with this hands-on earth science kit. Turn any stone into a shiny treasure! 100% SATISFACTION GUARANTEE - Join the millions of parents who have chosen our award-winning science toys and experience the Discover with Dr. Cool difference! Includes 2 year manufacturer warranty.