Why 2 types of Fiber clutch plates?

I have been trying to get some info on the differant types of Fiber clutch plates. My existing ones are solid fiber about 0.145" thick but the ones I see for sale are steel with fiber coating.. What's the differance and are the solid ones I have from Andover?? Thanks.

Barrnet or other aftermarket ones bonded / laminated .

I believe the solid fiber ones are made by Surflex. They also make the steel bonded ones much like the Barnett plates.
I'm not sure what type are being supplied by AN these days.

Thanks Ron. I'm calling in a order of things to OldBritts tomorrow & Fred speaks highly of the Barnett ones they sell so I'll most likely just add them to my order from them. I think they will end up being the steel ones laminated with fiber of some sort. CNW calls thiere Barnett ones "Barr-Flex" plates.... Don't know what that means.