The Valken Sierra Goggle is a low profile, thermal lens goggle that is very resistant to cold and heat. These goggles provide excellent resistance to fogging caused by temperature differences between indoor and outdoor, or between on-site and ambient environment. The Valken Sierra Goggles are perfect to be used as airsoft eye protection, or during other work related jobs against chemical splash, sun glare, dust, flying particles, and wind. The scratch resistant polycarbonate lens also provides 99.9% UVA/B/C protection, and the soft TPU goggle body conforms to facial contours to provide a full rubber eye seal. The Valken Sierra Airsoft Goggle features a special ventilation system with 14 indirect vents located at the top and bottom of the frame to allow air flow and heat release. We also recommend using these goggles in combination with either the Valken Kilo Mesh Mask, or the Valken Tango Mesh Mask for overall safety and protection.