These are the quality Carbide Bits that you can get from Whiteside. Definitely a step up from your typical Ebay/China bits. I've used this bit in about 8 projects since I got it, mostly for roughing 3D tree toolpaths. So far I haven't noticed any sign of haze under the gun. I am impressed. I'm used to $100 industrial grade end mills and wouldn't hesitate to use them on steel.