Durability This 8-80×56 High Master Wide Angle Riflescope, like all March scopes, is immensely strong to endure any severe condition. All March scopes are Argon-filled for internal stability and are fully weather-resistant and waterproof to at least 4 meters, and have passed impact tests of up to 1000G. The walls of the 34mm tubes are 4mm thick. Our 34mm body tube is simply just to make the scope extra strong. With its 4mm thick walls and the overall design, March-X and March-FX models are among the toughest riflescopes in the world. “X” in the classification name stands for 34mm body tube and “F” in the classification name stands for FFP (first focal plane). Fast focus eyepiece The diopter adjustment mechanism has been improved so you can adjust the eyepiece to your eye faster than ever before. Dials 0.05MIL Type One turn of both adjustment dials is 5MIL and one click is 0.05MIL.Elev...