Well, you could do a search as there have been 100s of thread on these heads. I use them and they are great. Fly true, cut big holes, and are very durable. This year I shot two deer and one raccoon with the same head. The coon I shot straight down and stuck the head 12" into the ground. On the second deer I broke a rib on entry and exit and the head was none the worse for it. I highly recommend them, as will most others that shoot them. The new blades are also scary sharp.