Image is for illustration purposes only. Actual part may vary.

LSV-5238

SAFTEY VALVE 250PSI

This is an ST-4 style air safety valve (also called a pop-off valve) designed to protect a truck's air compressor system from over-pressurization. It screws directly into the compressor head and is set to automatically crack open and vent air if system pressure exceeds 250 PSI, preventing damage to the compressor and air lines. You typically replace it when the old valve is leaking, stuck open, or failed closed, which can lead to dangerous pressure buildup. It's commonly used on heavy-duty trucks with Bendix Tu-Flo 550 or 750 series air compressors.