I have ordered 3 different brands of 40mm drill bits like this one. I use them to drill holes in candle holders for my Etsy shop. This is the best to date. Stays sharp long and I've drilled into hickory, oak, ash, hard maple etc. I haven't had much success resharpening but you will go a long way before it becomes dull and needs replacing. Best 40mm bit for the money I've found.