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Series No. 3908

The Protectoseal Series 3908 Pressure & Vacuum Relief Thief Hatch provides ready access to the tank interior for inspection, gauging or sampling operations. Integral, spring-loaded pressure and vacuum relief mechanisms open and close to permit only that intake or outlet relief necessary to keep interior pressures within working limits.

  • Product Specification Sheet - PDF
  • Installation & Maintenance Instructions - PDF
  • Size 8" API flat face flange
  • Lightweight, non-sparking aluminum cast cover for easy installation, operation and maintenance.
  • Precision lapped valve seat for exceptional sealing capabilities.
  • Lockdown feature used with either a padlock or lockout safety pin to prevent unintended access to the tank.
  • Pro-Flow® Web Based Sizing Application