Speedaire 4ZM28 Lockout Valve

Speedaire 4ZM28 is an inline air-line lockout valve that isolates the downstream pneumatic circuit for maintenance. It features 1/2 in NPT inlet and 1/2 in NPT outlet ports, enabling straightforward installation in standard 1/2 in lines. When the inlet is closed, the downstream air pressure vents through the exhaust port, providing depressurization of the controlled segment before service. The valve is rated for up to 250 psi, making it suitable for typical workshop and industrial compressed-air systems. As part of the Speedaire line, the 4ZM28 is commonly used in conjunction with other air-line components to safely depressurize downstream lines during maintenance tasks. Cataloged as Speedaire part number 4ZM28.