I have4 BH's I bought in the early 90's that are free spinning,thought they were pretty cool at the time untill I read they were illegle in alot of states because the say you can put poison on the shaft(ferrule)behind the blades.
I only used them one season and put them with all my other stuff,I still think about trying them,specking ofwitch you now have givin me a idea.

I think they were made by Thunderhead but not sure..........