Back in 1975 I had a leather motorcycle jacket with a similar claim. It had a center lining of aluminised mylar (?) with some kind of white filament woven in an

Back in 1975 I had a leather motorcycle jacket with a similar claim. It had a center lining of aluminised mylar (?) with some kind of white filament woven in and out of it. It was indeed very effective, and reduced the bulk of my inclement weather wear considerably.