http://www.jacksrbetter.com/shop/sierra-stealth/ Paired with a 20 degree 3/4 length HG Clone UQ, I can easily make it into the teens, with Lt wt Base Layers, socks and Fleece hood.
The UQ works so well for me, I'd be able to go warmer on the TQ w/o having to upgrade the UQ.
I'm a warm sleeper. Current kit gets me as low as I'm usually willing to go.
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