Manufacturer Name: Siemens Building Technology Product Number: 192-222 OEM Part Number: 192-222 Product Description: Rm Stat 7/30C 2 Pipe Da Weight:0.64lbs/290.3g Siemens 192-222 Pneumatic Room Thermostat is a precision for direct control in 2 pipe HVAC systems. The thermostat used in this system is pneumatically operated, this means temperature is regulated by air pressure var... https://www.partshnc.com/rm-stat-730c-2-pipe-da