The SINNER Steelhead II sunglasses are equipped with our newest lens technology:SINTRAST® lenses.The lenses not only eliminate high energy of blue light and filter 100% UV light, this lens technology is a combination of colour highlight and colour contrast.SINNER SINTRAST® lenses provide high clairity, high contrast, enhance details and are comfortable to your eyes.Resulting in a view without any distortion and maximum protection for your eyes.Steelhead sunglasses are specially designed for water sports.This means that the SINTRAST® WATERSPORTS high contrast lenses colour filter technology is focussing on water.The dark grey mirror category 3 lenses reduce glare, but not all, because you need to see waves coming in your direction.SINNER Free Insurance:After registration your sunglasses are 1 year free insured against theft, loss and damage.