In-line piloted unloader check valve combination with relief valve, part number: 56288756 for Ingersoll Rand. This is a solid brass valve that is manufactured by Conrader in the USA. This combination valve has a 1/2" inverted flare inlet on the top where your main line from the compressor pump comes in. The bottom port on the valve is a 1/2" male NPT that connects into the compressor tank. This valve comes equipped with a 325 PSI relief valve and a 1/8" female NPT port to install a throttle control valve if needed. This valve is factory set to kick on at 105 PSI and shut off / idle down the motor at 145 PSI.
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