Amazon.com.au:Customer reviews: Starter Rock Tumbler Kit for Kids– Includes Rough Gemstones, Polishing Grits, Jewelry Fastenings, and Instructions – Great STEM Science Kit for The Future Geologist, Boys and Girls Ages 8+
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This is a cheaply made product that we were not even able to use. On our first attempt to operate it the 'On/Off' button broke off and pushed right into the base of the unit. What a disappointment for my granddaughter! Don't waste your money.