Question How to tell what type of diving each BCD is/was designed for?

[TheCatFish]

Yeah that's exactly why I like steel tanks. For example, with my stainless steel backplate and wing setup, I can dive 3 different tanks: LP72, HP100, and Al63 (I use the Al63 in pool sessions with OW students). My weighting in my drysuit for single back gas is: Hp100 - 14lbs, LP72 - 16lbs, Al63 - 20lbs.

For my sms74 it is: 14lbs for both LP72s and LP50s.

My SMS75 maxes out at 18lbs of lead, I don't think I could dive drysuit with 2x Al80. I might do the 2xAl63 just for fun but I'd rather just do the 2x Lp72

A tip, those "3lb" pockets are marked with lead pouches in mind. A 5lb lead block fits very comfortably in those pouches though, extending the weight capacity to 30lbs. Would you need that much? Probably never, but just an option for playing around with your trim needs.