Batteries should be marked on the side, what voltage they are.
In the "16340" I've heard multiple mentions of the 3V rcr123a as well as the 3.7v 16340. (It's a common buzz pro question, people may have some 3v rcr123a around, wonder if they can use them instead of 3.7v 16340.) Check the battery for marking to determine which charger voltage to use.
18350s are almost certainly marked 3.7v, should be charged at 4.2. Again, just check the marking on the side of the battery -- if it says 3.7, then 4.2 is the right charger setting.