Steel 90s?!?

[Soggy]

My LDS is out of my normal rental tanks, MP Faber 72s (3300psi), which I love due to the fact that they are -6 lbs empty. In their place, they have some very old steel 90s. I *think* they are 3000psi fill or maybe a 3300. I can't find this tank anywhere on the spec sheets. Anyone have any ideas as to who makes it and what it's buoyancy characteristics are? The LDS told me they are similar to the 72s, but I want to make sure before I end up at my safety stop 5 lbs light.

 

[Lead_carrier]

From my recollection, you won't notice enough difference between the two tanks that it will matter. I believe the 90's run about 4-5# neg.