I don't know how old the Switchblades are, but I used them when I started bowhunting in the mid-seventies. They were only slightly larger than a Bear Razorhead and took a nice edge in sharpening. Without the ferrule extending to the front of the main blade,they'd occasionally bend during practice, but I never had a problem with that on an animal. I found them to fly nicely and cut well. It's Marv Clynke's long-time favorite.