Dimensions108mm x50mm / 4.25 X 2 in. Thickness of the lens: 1mm / 0.04in. Made of Premium Polycarbonate,our welding lenses exhibit exceptional impact resistance and abrasion resistance. This ensures clear vision and safe protection during prolonged welding sessions. Fit for every standard welding helmet lens filter shade.Before installing on the welding helmet, be sure to tear off the protective film on both sides of the surface. In order to make your helmet more suitable for welding, change lens cap regularly to ensure the best working condition, cleaning and protection. Package include 20 pcs of welding helmet lens covers.