Technical Information:

MK21 First Stage:

  • Air-balanced flow-through piston provides constant and effortless airflow unaffected by depth, tank pressure, or breathing rate.
  • Polished chrome plated marine grade brass body is close to 20 percent smaller than the MK25, making it an easy travel companion.
  • Unique thermal exchange design with external fins optimizes freezing resistance.
  • Two high pressure ports, one on each side of the body, allows the first stage to be positioned either up or down.
  • Standard "smart" hose routing cap offers four low pressure ports angled for more convenient hose routing (+/- 20º).
  • Optional hose routing cap increases routing configurations with four angled low pressure ports  (0°/30°) plus a fifth centralized high-flow low pressure port, ideal for technical diving.
  • Redesigned yoke allows for easier mounting on a cylinder, and redesigned cap protects internal components from water intrusion after the dive.
  • Available in either 3364psi/232bar INT or 4350psi/300bar DIN configurations.
  • Weight: INT 232 (oz/g): 26.2/744; DIN 300 (oz/g): 19.6/555.
  • Airflow at 2900psi/200bar: (l/min/SCFM): >7500/265.
  • Intermediate pressure (psi/bar): 130-142/9.0-9.8.

S560 Second Stage:

  • Air-balanced valve smoothes out the inhalation effort when diving at varying depths and supply pressures.
  • Lightweight techno-polymer casing helps reduce jaw fatigue and improve diving comfort.
  • Techno-polymer inlet tube contributes to reliability and long life.
  • High flow exhaust valve reduces exhalation effort to lower overall work of breathing.
  • User controls include a diver-adjustable inhalation effort knob and Venturi-Initiated Vacuum Assist (VIVA) dive/pre-dive switch.
  • Super-flow hose features an oversized bore (larger inside hose diameter) that allows more air to flow on each inhalation.
  • Ultra-comfortable orthodontic mouthpiece is easy to grip yet doesn't inhibit airflow.
  • Weight: 6.1oz/172g.
  • Airflow at 2900psi/200bar: 1850 l/min - 66 SCFM.
  • Maximum low pressure: 203psi/14bar.