Zcvtbye Rock Tumbler Kit,Rock Polisher for Kids & Adults,Includes 2 Belts,Bag of Rough Stones,4 Coarse Grinding,Finely Ground,Polishing Grits, Rock Tumblers for Adults - CREATE YOUR OWN GEMSTONESZcvtbye Rock Tumbler kit is a simple operation and a durable design,This rock tumblers makes it fun and easy to turn rough rocks into beautifully polished gemstones - ROCK TUMBLER KITRock tumblersis a great stem toys for kids to build their favorite gems by themselves. Rock polisher can improve childrens interest in geography and science, as well as exercise childrens patience. A rock tumbler science toy is the perfect birthday and Christmas gift for boys and girls. - ROCK TUMBLER FOR ADULTSYou can get a complete rock tumbler set, which includes all the tools needed to polish the stone: a rock tumbler, 4 pcs polishing grits, various rough rocks, jewelry fastenings, a tube of glue and a detailed instruction manual. - Durable Rock TumblersYou can set any stone grinding time from 1-7 days through the button, or you can stop and continue working with one button. After completing the set working time, the stone grinder stops automatically. Any questions you dont understand can also be answered in the detailed study guide booklet, which fully documents how to turn a rough stone into a beautifully polished gem. - ROCK TUMBLER GRITTHE PERFECT GIFE FOR ALL AGESOur rock tumbler science kit is a fun and educational Gems Hobby toy for all ages, Contains everything for making gemstones, rock collection gem jewelry, and gems decorations. Great kids&Adult gift for a birthday, or Christmas. Excellent STEM activity for adults, 6 years old up boys and girls.