Heavy duty 18″ manhole suitable for oil field service trailers. Tested to 36 PSI and exceeds DOT 178.345-5 specifications. When installed with the #2186 vent, the products exceed the DOT 412 requirements. Outstanding safety feature of “Ball in Socket” cam handle design is standard. Options included Viton cover gaskets, 4″ or 7″ tall weld-in collars and Buna N or Viton base gaskets.