Fits over most prescription spectacles – low cost alternative to safety prescription eyewear.Side arms graduate from hard to soft material. Gently grips the side of the head not behind the ears – making to comfortable to wear two pairs of glasses. Hi resolution lens – improved clarity. Polycarbonate lens for optimal impact protection and high levels of safety. Unique frame design. Permanent anti-fog coating on the inside of the lens and scratch resistant on the outside. Increased safety and durability. EN166 1F KN.