Forney 57012 Lens Replacement Hardened Glass, 4-1/4-Inch-by-2-Inch, Shade-12 Replacement hardened welding lens Fits most brand name helmets using 4 1/4-Inch x 2-Inch window opening Meets ANSI Z87.1 safety standards High quality material offers superior protection from dust, weld spatter and impact Provides 99.9-Percent UV-AB protection from the sun