Polycarbonate Filter Plate, Compatible with Brand Sellstrom, Compatible with Manufacturer Model Number S29901, S29911,, Compatible with Series 290, Features Impact Strength And Optical Clarity, For Use With Sellstrom And Most Competitive Helmets, Material Polycarbonate, Plate Length 4 1/2 in, Plate Thickness 0.12 in, Plate Width 5 1/4 in, Standards ANSI Z87.1, Welding Shade Designation W12