Gas Tight Fogless Goggles feature a neoprene molded rubber frame with a replaceable .050"-thick clear acetate lens. Top and side perforated screens give maximum ventilation. Adjustable headband. The Gas-Tight Goggle is the same as the all purpose but without ventilation screens and strap slots. Nuts and bolts on front of frame and vinylite lens for acid resistance. These goggles cannot be worn over glasses. Chemical Splash Goggle protects against hazardous liquids and dust. Four indirect vents offer unobstructed side vision and air flow.