The Square is a simple easy wearing style. Good clean lines and very comfortable to wear. A style that feels at home anywhere. Conforms to EU Standard BS EN 1836 : 2005 + A1:2007Lens:S11 Grey Polarised Cat.3 Karbon8 optical Class One lens provide MAX UV protection. Distortion free and virtually indestructible.Frame:BLOC frames are hand finished flexible lightweight and designed for comfort fit and performance. The spring hinge offers both quality and durability. The fully adjustable hypoallergenic nose pads and the non slip hypoallergenic temple tips are designed for comfort and fit.