I recently bought 2 comet
marine propane tanks over the
Internet at Amazon. I filled 11lb of propane in each cylinder. It seems it has a
steel liner inside wrapped with a composite fiber and then a very nice plastic jacket. It also has a level indicator on the top of the valve, but I didn't use them until the end to know if it works or not. Now it shows green. The cylinders look very strong and they cannot damage the
boat. The cylinders are non-corrosive too.
For the information I was able to gather (and I'm one of those guys that look for everything), it seems to be that this is the best compromise taking into consideration
reliability, non-corrosive, weight and handling.
These cylinders come with the OPD valve with the usual connections. I saw in the
Internet that they use these cylinders in
Australia,
Europe and
Africa but I'm not sure on the connections.
These cylinders are US and
Canada approved (DOT) and you can download all the technical information on their website cometpropane.com
Good luck!