POWERFUL LIGHT RESERVE 58 mm OBJECTIVE LENS DIAMETER Compared to riflescopes featuring a 56 mm objective lens diameter, 58 mm provide an additional light yield of 7%. This allows use of a higher magnification with better detail recognition in deep twilight or at night. Blaser 420x58 iC The twilight specialist superior for sitting game and when hunting in the very last light. Excellent light gathering characteristics far exceed what other scopes provide in low light conditions. Making the impossible long range shot possible. High contrast and optimal sharpness of detail, especially in the last light 58 mm lens diameter means more than 7% additional light yield compared to a 56 mm lens 20x magnification provides invaluable services to safely identify game and gives the ability to interpret and understand targets at long range.