Found this under great planes fiber glass listing. not sure how to read it though?
COMMENTS: Common usages: Cowl & Wing Center Wing Center Wing CenterWheel pant Up to .40 Up to .60 Up to .90GPMR1052 Heavy (1") *GPMR1054 Medium (2") *GPMR1056 Heavy (3") *GPMR1058 Heavy (4") *AXY 7/12/97ir/jl