Sorry if this has been posted before, but you can now get an adapter for fcs fins to fit futures boxes
www.wasabisurf.com
I bought a set of the original ones. They were handmade out of resin and thin alloy sheet. Quite fragile if the fin box was a bit tight. I wrecked one, and they sent me a free replacement pronto. I wrecked another couple and gave up.
Not too long ago wasabi contacted me to see if I was at the same address. They were sending all their original customers a free set of the latest flash ones. Sure enough they turned up not long after.
Now that's what I call customer service! 
