I was just wondering if anyone out there knows whether or not the D.O.T. has certified Poseidon tanks. I use a few 8 L and 10 L tanks, but I know they won't allow in the States due to no DOT stamp. Are 3500 steel tanks the highest one can get? I'm from the States, but all of my diving has been overseas, so I don't have a clue. My real favourite is the Poseidon 8L tank. Small, but with more or less the same as a regular Aluminium 80. Thanks, just curious.