Review on 🔧 YUFUTOL 5 Pcs Carbide Burrs Set for Aluminum - Extended 4.4" Long Reach Carbide Rotary Burr Files Set with 1/4 Inch Shank for Die Grinder Drill, Metal Carving, Polishing, Engraving, and Drilling by Charles Mathews

I use these for porting aluminum cylinder heads. The long shanks are great for accessing ports without the grinding chuck touching the walls. They cut well, don't clog and show no signs of wear. The only reason for 4 stars is that the tip and base of some bits are very sharp and will cut very deep and aggressively unless the angle of your bit is perfectly angled to the material. Even the rounded tip in the picture has a very slight bulge at the rounded end, it will clip off very quickly if you're not careful. The flat end is much more grippy. Overall good pieces, I like long thighs and so far they serve very well.