POC’s Carl Zeiss lenses are made of polycarbonate (PC) and have superior performance. All combinations of tints and mirrors have been carefully selected to minimize internal glare and to utilize the full effect of the base tint benefits.Important. Due to the changes in lens thickness, old frames and lenses are incompatible with the new frames and lenses for Iris, Retina and Retina Big. All new lenses have a + sign on the lens. Technical Features:- Lens By Zeiss- Black (No Mirror), Vlt 6%, Category S4- Bronze / Silver Mirror Vlt 12%, Category S3- Persimmon / Blue Mirror Vlt 25%, Category S2- Pink / Gold Mirror Vlt 31%, Category S2- Pink / Bronze Mirror Vlt 28%, Category S2- Grey / Purple Mirror Vlt 33%, Category S2- Persimmon / Red Mirror Vlt 35%, Category S2- Persimmon / Green Mirror Vlt 9%, Category S3- Sonar Orange (No Mirror) Vlt 45%, Category S1- Yellow (No Mirror) Vlt 63 %, Category S1 + Lens:- Ripel - All Zeiss Lenses Will Have Oleophobic And Hydrophobic Treatment Which Ensures Water, Dirt, Oil And Dust Cannot Stick To The Surface Of The Lens- Wider Tint Range - Easier To Find Your Personal Favorite Lens Tint Based On Your Choice For Eye Comfort And Aesthetics- Low Light Filter - Higher Vlt On The Poc Specific Sonar Lens Provides Better Performance In Low Light Conditions- Thicker Lens - 1,8 Mm Lens Throughout The Range For Enhanced Durability And A More Robust Lens Attachment, Especially For All Iris, Retina And Retina Big