NOS, New in Box, 2 rounded Corners Rectangle Vintage Frost Shields. From Streamline/Chryco Engineered Parts and Accessories.
Gaskets are disintegrated from shelf life. These Gaskets can easily be reproduced.
Frost Shields are rectangles of glass or plastic with a raised adhesive strip around the entire edge. You stuck them to the inside of your car windows and they prevented condensation from forming and becoming frost. If you want to get technical about it, here's a 1941 patent for a frost shield that explains how the work in excruciating detail. Frost shields burst onto the automotive scene in the winter of 1926 - 27, long before front and rear window defrosters were a gleam in the eye of automotive engineers. They were soon a standard part of your basic winter tune-up, along with radiator grill covers and winter anti-freeze.The first shields were actually a thin piece of glass that came with a rubber gasket and a jar of adhesive. It wasn't until the late 1940s that celluloid versions were advertised. Soon after, there were electric versions that used heated wires running through the glass to keep them frost free.