Valve is normally closed without an independent poppet. A 2.625 inch inlet is standard. The outlet is 2.50 inch with a 4.50 inch round flange for attachment to the compressor. The inlet and outlet are in line. The poppet seals with a special Teflon o-ring mounted in the body. The valve material is an aluminum body, aluminum poppet and piston with a steel spring.
The rated pressure drop is 4 in_wtr (1 kPa) @ 200 scfm (5.6 m³/min) airflow. Here a scfm is one cubic foot per minute of air at 14.696 psia (1.01325 bara), 60°F (15.555°C) and 0.0% relative humidity.