I’ve used a homemade 2.5 oz Climashield synthetic blanket over a sleeping bag and it works well, adding perhaps 10 degrees at most. It feels nice to have a looser, roomier second layer, to me anyway.
You probably already know most of this but Nunatak and Timmermade say a 2.5 oz Apex overbag can add 15-20 degrees of warmth. This estimate feels right to me, at least when it’s new. The 3.6 oz Apex would provide more insulation but may get packed out sooner?
The outer shell of the blanket sometimes feels damp but not the down underneath, which is what many acknowledge is the strength of this setup. In any event, it does add warmth.
How do you like the Newt?
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