The MK11 EVO/C370 is a compact, dependable air delivery system that makes diving fun, wherever your travels take you. The new balanced diaphragm MK11 EVO features an innovative double spring layout, forged brass body with thermal fins and protective plastic bumpers to ward off scratches. The compact C370 offers convenient user controls including a diver-adjustable inhalation effort knob, a coaxial dive/pre-dive lever and a large, easy-to-activate purge button.