20Pcs Diamond Mounted Point, 6mm Ball Head, 3mm Shank, Diamond Grinding Bit Rotary Burrs, for Jade Stone Jewelry Ceramic Carving Polishing

Used them on aluminum and didn't dull or clog.

For the price these diamond bits can't be beat. I do advise using water to cool the bits down if using on glass or mirror. I usually use them on drinking glasses & mirror, this was a first on tempered auto glass. I will continue to order these in the future.

Using it to trim plastic works great

Dulls pretty quick.

I just think the quality isn't that great, tends to wear down after a few uses

Works well. Very happy.

Good consistency in the grain. Smooth grinding

Somewhere, somehow, this package was relieved of a single tool before it was boxed and shipped to me. The label is plainly marked 20 PCS, at a glance the empty slot within the packaging clearly shows a missing tool. Hopefully this is an isolated incident.