Spectron 4 is a mountaineering lens, blocking 95% of visible light; Spectron 3 blocks 88% and is suited to many activities; both are lightweight and shock resistant
Flash treatment improves visible light filtering with a mirror effect on the lens; anti-reflective coating provides relief from glare off the back of the lens
Complete, full-spectrum UV protection
Curved temples provide maximum coverage and removable side shields let you adapt to changing conditions