The ROSS CONTROLS DM2 category 4 safety exhaust valves are used in safety systems for machine safeguarding applications. The DM2 Double Valves with TOTAL Dynamic Monitoring & Memory combine the tough, dirt tolerant, wear compensating characteristics of poppet technology with new double valve features in response to the changing demands of safety standards and regulations. Memory, cross monitoring, and air- flow control functions are integrated into two identical valve elements. DM2 valves lock and inhibit further operation upon sensing an asynchronous movement of valve elements during actuation or de- actuation. To further enhance safety a dedicated reset signal is the only way this valve can be reset into the run mode, thus eliminating accidental resets. It also features a feedback switch for integration with the controls system for troubleshooting assistance. These unique valves are available in several port sizes.