dh@. wrote:

A lot of people around here have covers made for their
boats that will go around the front deck or a rear deck,
custom made of fabric and heavy flexible clear plastic
sown together, and it usually snaps and zippers in place. I
don't know what to call them. What I'm mainly interested
in is the plastic. Can anyone tell me some specifics about
it so I have an idea what to look for, and maybe even
where to get it?

Weather canvas.

Tent maker.

Or, do your own, all it takes is a needle and palm.

We got out material at a fabric store, and made frames from semi
flexible chiney rod fibergalss material.

Some one here has made his bimini cover (intended primarily for a
sunshade) using old fire hose inflated with air for a framework.
Says it works good, and ya can't hurt you head on it.

Yup, really.

Terry K