The Flame King 40LB Propane Tank is pre-purged and vacuum-ready for filling of propane avoiding you the cost and headache of purging your new tank. It is built from high-grade welded steel and powder-coated for rust prevention. For your safety your tank comes with an OPD valve to prevent overfilling as well as x-ray and hydrostatic tested. You can be sure to transport safely both in the US and CA as they are DOT and TC (Transport Canada) certified.