The M-20.2 is a self-contained, closed-circuit breathing apparatus. The compressed oxygen delivery system activates automatically when the device is removed from the clear case. The demand regulator allows the user to inhale immediately from the device when donned and provides up to 100 liters of oxygen flow during high work rates. The clear case allows the crewmember to quickly visually assess the operational readiness of the device. The M-20.2 can be either belt-worn or stored and is used in multiple markets to protect the user during escape from toxic, or oxygen-deficient atmospheres.