IP68&IP69K &MIL-STD-810G Certified Dare to Challenge Any Extremes From the R&D,selection on the materials and processes to the reliability tests & quality controls,BV4900 is under comprehensive and strict check to ensure the outstanding ruggedness and well survive in rough environments.Tough Space Capsule Design Sturdiness Never Cut by the Crafted Appearance The back cover design derived from the internal structure of Space Cap- sule gives a simple and streamlined look with symmetrical aesthetics.Moreover,while with a robust build,BV4900s is only 13.7mm thick and 261g light,not as bulky and clumsy as other rugged phones.BV4900s combines the Android 11 Go OS and developed Doke OS 2.0 to enable smoothness and efficiency.While enjoying the similar experience to Android 11, you get an easier operation and smarter controls brought from Doke OS 2.0.