For divers seeking reliable performance in an uncomplicated air delivery system, the MK11 EVO / S270 is easy to use, compact and durable. The balanced diaphragm MK11 EVO delivers effortless airflow unaffected by depth, tank pressure or breathing rate. The compact S270 provides smooth breathing performance in an anti-scratch design that&&';;s able to handle years of hard use. Compact, air-balanced diaphragm design, MK11 EVO delivers top performance and reliability Forged brass body comes with metal fins to improve thermal exchange plus plastic bumpers to prevent scratching Innovative double spring layout increases performance while contributing to overall compactness Two high pressure ports are set on a 15-degree angle for convenient hose routing. Four high-flow low pressure ports increase airflow while maximizing hose routing options. CE Certified adheres to the latest EN250A European Standards for all diving conditions including extreme cold water. Product Resources Read First Manual English. Product Manual Frequently Asked Questions