The Nano Puff Pullover is so Good it Stinks

My Patagonia Nano Puff Pullover is wet. It smells awful....or maybe that is me. I was breaking trail uphill in nothing but a base layer. When I stopped I pulled it on and then put my DAS parka on over it. I kept the Nano on as I started down and the added warmth helped my base layer dry while I warmed back up, transferring all the moisture to it.

Tree skiing in the Nano

Worn over a soft shell for added warmth in wet snow in Mount Rainier National Park

Good thing it is so easy to wash.

Jen and I both have Nano Puff Pullovers and we bring them on most trips. In warmer conditions mine is often the only piece of insulation I use. I clip it on my harness for alpine climbs and throw it in a small pack for trail runs or bike rides in case I sprain an ankle or break a chain.

A perfect light insulating piece for summer backpacking

In the winter it is a key layering piece. It is cut boxy enough to fit over several layers yet is compressible enough to fit comfortably under a shell.

It has held up well in the year and a half I have had it and has only a few slight snags despite being worn for bushwhacking and tree skiing when I was too cold to take it off or move it under my shell.  I also wash it regularly which is something that is hard to do with a down piece. (I use a Granger Outerwear Care Kit which includes laundry soap and a DWR refresher to keep the Nano water resistant. Don't use standard detergent! It works by wicking water into the fabric and ruins DWR. Granger or McNett products work and smell much better than NikWax but are harder to find.)

The Nano puff isn't very breathable, and for sustained activity in the cold where you will be moving a lot of sweat, you are better off with a combination of thin fleece and/or soft shell (I like the Patagonia R1 Hoody and a windshirt or thin uninsulated soft shell like the discontinued Patagonia Ascensionist).

Worn on a cold morning in late summer

The Nano is perfect for stop and go activities. I keep mine on while climbing the first pitch on a chilly morning or when leap frogging down a slope on skis or skiing lift served laps. I'll often wear it after a rest break and stop briefly to peel it off before I get too warm.

Used like this or worn under a parka it can soak up the moisture from your base layer, leaving you dry and comfortable. (This doesn't work as well in humid Cascades conditions...bring an extra base layer for that). This winter in the colder dryer Rockies I plan on experimenting with the Nano as a sacrificial sweat absorbing layer under a thick down parka.

Jen breaking trail in her Nano

Several other companies make similar pieces that I haven't tried. The key features of the Nano Puff are the loose fit for layering, 60 g Primaloft One insulation (warmer per weight then primaloft eco or sport), light weight due to minimal features and the ability to stuff in its own pocket for clipping to a harness.

Patagonia made a similar pullover a few years ago called the "Puff Ball" which was discontinued in favor of heavier garments with full zippers and a more flattering, less versatile cut. Hopefully the same fte won't befall the Nano but if you want one you should pick one up soon. They frequently go on end of season clearance for around $100.