Boasting the same great features as the standard Vise®, The XL version is the first pair of (you guessed it) EXTRA-LARGE Heat Wave frames specifically designed for the ones with larger than average heads.  We took the time-tested design of the Vise® and added an extra 10mm in width and jacked up the ride height to 5mm to provide Godzilla-like, larger than life comfort and coverage. About The Vise® Z87: features an all TR90 construction and tightly holds form and function together, as the Vise® Z87 meets ANSI Z.87 mass-impact requirements (and Z87+ with add on side-shields) featuring 1.9mm thick lenses to aid in protection against basic impacts and flying debris, which enables the Vise® to transcend just that of a regular pair of sunglasses. Meets Z.87 Requirements, and Z87+ with add on Side Shields Our lenses are injection molded from thick 1.9mm shatter-resistant polycarbonate that is built to withstand Z87 Mass Impact Standards. Add on optional side shields for additional lateral protection to meet Z87+ standards Each pair of Vise® Z87 is boldly marked Z87 on the frame, arm and lens. Disclaimer: Removing arms, and or changing configuration in any way voids Z87 compliance. Lens Technology: 1.9mm thick Polycarbonate lens that meets or exceeds impact requirements for Z80.3 standards, injection molded to the highest standards and tested to ensure optimal clarity, along with color and light transmission standards. We use only the highest quality polarizing filters on our lenses for optimal glare reduction and supreme clarity Lenses are U6:L3 UV400 - 100% UVA / UVB blocking Hi-Vis Yellow Lens VLT = 89% / Cat 0