Blower Relief Valve Vacuum Capabilities Vacuum Preset Limit 232 in wc Outside Diameter 5.7 in Inlet Size 2 in Inlet Type NPT Compatible Manufacturer Part Number 2EPN9 2EPP1 2EPP4 2EPP5 Compatible Grainger Part Number 2EPN9 2EPP1 2EPP4 2EPP5 Maximum Operating Pressure 28 in Hg Minimum Operating Pressure 1 in Hg Maximum Operating Temperature 400 Degrees F Minimum Operating Temperature -20 Degrees F Overall Length 7.31 in