Maxitrol M620 1 Gas Valve Els PW 17895 Automatic System Recovery: Features an Automatic System Recovery: Features an auto reset mechanism at 125°F Versatile 3 8 inch Drive: Features a standard socket connection for use with existing ratchets to provide controlled torque during disassembly the Maxitrol M620 1 requires a compatible electronic amplifier or signal conditioner to provide the DC voltage necessary for modulation This Maxitrol modulating valve is essential for maintaining consistent discharge air temperatures in makeup air units and space heating equipment where precise gas flow control and high turndown ratios are required