Mine is made of furniture grade plywood, covered in resin and removes with 6 pins (no tools required and can be on/off in 2 minutes. Aluminum mounts bolted to the body and splitter along with 2 center support rods. It's about as bullet proof as you can make them, been off track many times and you'd never know it. I had the Flatout splitter and I spent more time repairing the splitter, bumper and front fender as it was very sensitive to any off. I believe the ISC splitter is for S4 front bumpers only?

Some details and pictures on mine here http://www.rx7club.com/showthread.ph...plitter&page=4 - more posts later in the thread but I never did get around to doing the "how to" I said I would - got too busy.