L13
Contributor
I recently did 3 cenote cavern dives in one day using a 3mm. By the end of the 3rd dive I was getting cold enough I wished I had a 5mm.I assume you are planning cavern dives and not cave dives. Cavern dives are much shorter, and you may well be fine in the 3mm suit--but not by much. For 2 hour cave dives, I have been fine with my 5mm suit. It is getting old, though, and I may use my 7mm suit on the ext trip.