SANHOOII 50in1 Power Rotary Tool Accessories Rotary Tools Set Diamond Burrs 3.2MM Shank For DIY Carving Polishing

These are great diamond coated bits, particularly at this price. I had some pottery glaze which flowed over the bottom of some pieces I'd fired, and had given up on being able to use them (though they were otherwise beautiful). I saw a discussion forum where smoothing with a Dremmel rotary tool diamond coated bits was suggested as a solution, so I ordered these and they worked great. The resulting surface was like sanded glass, not polished smooth (which would need an additional step), but still very useable. More importantly, I did not notice any degradation in the bits following grinding, which suggests that they are well made and will last a long time. Be careful to wear a dust filter (in my case, from silica dust) and use eye protection -- I did the grinding outdoors so that the fine dust could be safely dissipated.