Review on Utoolmart Straight Corundum Engraving Polishing by Sean Garrison

Update: Too much vibration after a bit of use and the sandstone falls out of the chute, glad you have 100 of these, you'll need them. Of course some of them are a little off balance, but there's nothing my two Dremel/rotators can't handle. The 10mm is perfect for my hobby RC DIY projects. I use them on metal, wood, plastic, rubber, yes I break some of them from time to time when the material it's grinding gets stuck in the bit and builds up, but they're cheap enough that I just use them drop and move on. with another bit. Could be better but due to poor quality control because "Made in China" took off 1 star, they are not balanced at all, cheap manufacturing process.