For vinyl-a double
layer of vinyl, plus an additional layer of tough nylon mesh
for reinforcement. Also, two piece, smooth, rust-proof anodized aluminum
grommets for positive protection against rusting and torn tops.
For fabric-a triple
thick top hem consisting of a double layer of fabric plus an
additional layer of tough nylon mesh. Finished with sewn buttonholes
or, if specified, smooth, two-piece, anodized aluminum grommets.