3M Speedglas Inner Protection Plates are replaceable spare parts for 3M Speedglas Welding Helmets and are designed to protect the welding filter.3M Speedglas Inner Protection Plate is a spare part for the 3M Speedglas Welding Helmet that protects the welding lens from spark and welding spatter. Replace when 3M Speedglas Inner Protection Plate becomes damaged or too dirty to clean. Regularly clean with a lint-free tissue or cloth, for example the 3M Cleaning Wipe. For maximum safety and comfort, regularly check your equipment for worn or damaged parts.