Last Saturday we had a big cold front for here and i tried wearing some of my duck hunting gear, man it wast just way to bulky. Sunday morning it was around 18 so I tried the layer method. Long insulated underware bibs and 7 shirts or sweaters, with scent blocker as a top layer. it wasn't as bulky and i was very warm. Got my 1st buck with a bow. So from now on it will be layers.