Why not use a transfer whip from a large scuba tank, just top the Inspiration bottles up as you go?
I just split my old twinset and use one as an O2 bank, saves buying yet MORE tanks to keep in test, grumble grumble....
BEN
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Know your PPO2, Pre-breath, Use checklists, Validate cells at 6mtrs, Use pure O2 at or near surface, Use a BOV, Don't dive Solo, Change Slime and Cells as recommended by Manufacturer and RTFM!
Beware Fridge Suck!
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