Monogoggle - Clear Anti-Fog Lens - Indirect Vent See why Monogoggle outsells the competition. The Monogoggle s superior ventilation system creates increased air flow across the lens, minimizing condensation and fogging. Optical grade polycarbonate provides impact protection. Comfortable plastic nosepiece fits a variety of facial contours, providing comfort and protection. Two piece frame makes replacing lens easy and economical. Monogoggle VPC has a 35% larger lens area for easy fit over most prescription glasses. Meets ANSI Z87.1-2003 standard for high impact eyewear.