shield of plastic or metal mesh, mounted with a support device at some distance from the face protecting it and possibly also the neck from splashes or droplets of hazardous substances, eye protectors consisting of curved, generally transparent polycarbonate screens supported from above by a plastic harness fitted over and round the top of the head and protecting the face entirely; heavier types used for welding are made of fibre glass or metal with a rectangular window of dark green toughened glass in front of the eyes