3 flue variable helix, I’m stoked. I’ll probably pick up those stealth bits you use next time I order just to see if theres a difference. I’ve been using a stub 3 flute AlTiN coated bits for a while now. I heard they’re both good and bad for aluminum milling. Most people seem to think its good, but I read something a while ago that said it was bad, something about not providing enough lubricity. Oh well, I’m competent enough now to never snap or chip a bit anymore so I guess I can play around with coatings and see what works best for me.