AquaLung optical lens for Look mask. Look masks can be easily transformed in optical masks. Original lens can be disassembled and replaced by the optical prescription lens required. Look lenses range: negative: from -1,00 up to -10,00 (by 0,50 steps) positive: from +1,50 up to +3,00 (by 0,50 steps) Negative lenses are symmetrical: the same lens can be assembled either on the right or the left side. If you order different strength lenses for different eyes, please mention in the order which lens is for certain eye. Please, note that the price is per one unit.