[EricH]

The standard tests for what clear plastic is are as follows (choose one):

A) Drill a hole. Plexiglass cracks; Lexan (polycarb) doesn't. There are ways to avoid the cracks, but in general, this works.

B) Clamp one end to a solid surface and hit it with your biggest hammer. If it breaks, it's Plexiglass.

C) If it still has the backing on it, read that.