Designed to protect. Designed to fit. Ultra flex glasses from Stihl provide comfort with a form-fitting frame. Whether you’re a homeowner or professional landscaper, these mirrored sunglasses feel like they were made just for you. The lenses are made from optical-grade polycarbonate and block out 99% of harmful UV rays. The glasses are also hypoallergenic and feature a vented rubber nosepiece to reduce slippage.