This Dead Man's Valve Type MDMV is utilized for extremely quick oil or water drain. Particularly for pressure-draining both oil and water from closed-loop cooling systems, this valve is developed. In order to safeguard the operator against refrigerant leakage that may accidentally discharge gas into the atmosphere, the valve self-closes upon release of the handle. This Dead Man's Valve Type MDMV was developed in accordance with all safety requirements specified in both national and international standards for commercial cooling.