These are two from my collection. The one on the left I think is what KY Clint was talking about, it uses razor blades, and has four blades that lock together with two "O ring" looking things. As for the one on the right, I have no idea who made it. It has 5 blades, and the section that the blades are attached to is seperate from the center piece with the threads. Theory was that as your arrow was spinning in flight, the blades would remain stationary, and thus your arrow wouldn't plane left or right. Kind of the opposet of what Crimson Talon broadheads do. The threads on this particular broadhead are broken off, from the time that I tested the theory that they don't plane. Obviously, they did.
My grandpa tells me that these 5 and 6 blade broadheads worked really well though.