This patented design access cover offered by Tompkins Industries (US7721904 B) and features positive O-Ring bolt seal; full-bolt torque load rated; heavy-duty grade 50 steel construction.  Designed for air impact gun installation and can be installed above and below fluid level. Buna-N Temperature Range: -35°F to +250°F; pressure tested up to 35 PSI; 500-degree powder coat O-rings and gaskets available; self-centering anti-rotation inner plate does not drop during disassembly.

Contact a CSR for pricing and availability.  CAD drawings are available at https://www.tompkinsind.com/resources/cleanout-cover-cad