Bloc eyewear cobra shiny black sunglasses s11 grey polarisedcat 3 lens description the ideal partner for any demanding activity engineered to enhance performance and provide total protection conforms to eu standard bs en 1836 2005 a12007 lens s11 grey polarised cat3 karbon8 optical class one lens provide max uv protection distortion free and virtually indestructible frame bloc frames utilises tough and compliant karbon tx core injected frames and are hand finished the