Crane Composites FRP (Fiberglass Reinforced Plastic) if my memory serves me right. Not sure exactly which product out of the many listed, but it's one of them. Bclemens had sent me the info a while back.
John and Rebecca Dickson
Emma-7 / Little John-5 / Iva-1
Full Timing Again, Rev B
2013 Ford F-350 Lariat CC LB PSD
2015 SOB TT - With OC's Awning Poles (#8)
At least in Heaven, RVs will be perfect, and I won't have to keep fixing them.