":::::A photo showing both would certainly help. I guess my concern is over 'typical recreational diving'. As PADI mostly uses 32% and 36% mixes, and usually doesn't exceed 30m, them MOD isn't really the important thing. On a 'typical' PADI dive expedition, It is very unlikely that anyone on the boat is going to dive below 30m - and if they do, they'll be experienced, and won't be silly enough to mix up tanks. Also, I suppose, we're more concerned with the distinction between Nitrox and non-nitrox tanks than the exact MOD; the Nitrox divers will check the details of their own tanks (with an oxygen analyzer), and put their name on their tank. (And, in most cases, they'll prob all be 32% anyway)   

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