As stated in the subtopic I'm specifically interested in under a 3.5 mm crushed neoprene type wetsuit (Waterproof brand, D10 Pro), as that's what I've got arriving shortly.
For my first real "open" (well, cavern, but certainly non-pool) dives with it I'll be in a mine at 58 deg (F). For that temp I'm thinking even just a thin set of polypropylene undies as more of a moisture transport/wicking material vs. a lot of airspace "loft" or "fleece" layer should be enough. Prior experience has mostly been in the 70deg (F) plus range. Last trip, 3-tank days with 1 hr per dive at 78deg water temps with a 2/2 shorty I was getting a bit chilled, but in general I don't think I'm that cold-natured.
I will be wearing a hood and wet gloves - both probably 3-5 mm thicknesses.
In the long run also interested (but no immediate plans) in the Pacific NW or even joining one of the WP Alaska trips. For that I'm guessing "go for broke" with undergarments, even under neoprene vs. trilam...
Edited by rtrski, 22 March 2012 - 07:51 AM.