The Olympus E-M5 Mark II Camera is pretty awesome. It has a 16MP Live MOS sensor, a 5-axis voice coil motor image stabilization system, and built-in WiFi. The camera is not waterproof though. The Olympus PT-EP13 Underwater Case is designed to keep this camera protected underwater. It is pressure resistant to water depth of 45 meters.
The case is compatible with 9-18mm, 14-42mm II, 14-42mm II R, 12-50mm, 45mm, 60mm, and 75mm Olympus lenses. You will be able to shoot with the flash that comes with your E-M5 Mark II.