Tank ID help

[Katch]

Why is the black one so much longer than the unpainted one? They are both supposed to be HP100's. The short one is an X7-100 and matches all the dimensions on the charts for the PST E7 100's. The black one is older, but several inches taller (about 28") and has a narrower neck. They both have the same diameter too. The numbers on the black one: DOT E9791-3500 TP5250 C528494 (then a "P" symbol that may be "PST") CDI.



Standing side by side, its hard to believe these tanks hold the same amount of air.



Steve

 

[Leslie Sapp]

It's one of the old 7/8" valve PST 3500 psi tanks. If it's 28" tall, it's probably a 120.
Take some good measurements on both tanks and then compare them here.

 

[Katch]

But the owner of the black one (who has owned 2 of them for years - set up as doubles for cave diving) claims that it is also a 100. I don't think the Huron Scuba site has the older tanks listed-I could be wrong though.

 

[Scared Silly]

pst 120

3500

122.5

7.25

27.87

39.2

-1.3

-10.3

 

[Katch]

That's what I said, but he insists that they are 100's. He said there are some cave diving documents showing these tanks exist, and will show me next time I stop by.

Maybe it's worth betting him a beer or two.