This ad. doesn't seem to make a lot of sense to me. Maybe it's my liberal arts education creeping up on me...
Shouldn't it read "68ci/4500psi" not "68/4500ci" since the first number is the volume and the second number is the pressure value?
Also, shouldn't it read "payload 68-4.5k compressed" not "payload 68-45k compressed?"
Afterall, it's 4,500psi, not 45,000psi.
Is there anything different between the two tanks aside from color?