The MEPCO Spring Packed Radiator Valve No. 740 applies to all types of steam heating systems with pressures up to 25″ Hg vacuum to 150 PSIG. The same valve can be applied to hot or chilled water systems at pressures up to 200 PSIG. It provides a positive “on” or “off” control for any type of heating element or radiator. The heavy coil spring keeps packing tight around the valve stem. Dial arrows on the handle clearly indicate the direction of “on” and “off” and divisions on the dial make adjusting the valve easy.