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Marmot Bantamweight Rain Jacket Review

Sets a new high bar for ultralight rain protection!

By: Jason Hatfield + Save to a List

If you play or live in Colorado's mountains you'll quickly learn an important summer mantra "always bring a jacket". Afternoon thunderstorms and showers are fairly regular June through August and can seem to come out of nowhere on a blue sky day. As a trail and ultra runner, that usually means I'm trying to decide whether it's worth bringing a full heavy rain jacket or something lightweight that's "water resistant". For years that's typically meant I bring my ultralight wind jacket on shorter runs and whatever lightish rain jacket I have for big mountain runs. Sometimes I make the wrong choice though and have had a couple near-hypothermia events after being caught by a sudden hail storm sneaking over the continental divide.

Now with the Marmot Bantamweight Jacket I don't have to make that choice! While there are a few other ultralight rain jackets on the market this is the first one I've used that has most of the features of a normal one while weighing only 5 oz! I've spent the past couple weeks taking it on trail runs and bike rides to test it out and while I didn't find any rain (Denver has decided to stick more with snow so far this spring), I really came to appreciate its features and wind-blocking ability.

The first thing you'll notice and my favorite feature, the zippered pockets. Not something you typically find in this weight class, the zippers are waterproof and the inner mesh is stretchy and soft. They're great for throwing your gloves and hat in after you've warmed up or snacks for the trail, and personally I just like to rest my hands in jacket pockets when standing around. The left pocket also has an interior mesh pocket that will fit any size phone and more. That same pocket serves as a stuff pocket and is the easiest one I've ever used on a jacket, no forcing the last bits of fabric in while trying to pull the zipper without catching it.

Another great aspect of the jacket is the slight stretch material that moves with you with running. It's a very thin fabric so you don't want to use it for any off-trail exploration through heavy vegetation; but it doesn't feel fragile or require babying for normal use. The waterproof Pertex Shield material did really well in a 15 minute test in my shower, the seams are taped so no wetting out or leaking. It's an ultralight rain jacket though, if you use it in all day heavy rain it will wet out quicker vs a heavy 3-layer Gore-Tex jacket. The material also feels nice on the skin when dry.

Like all rain jackets, if you run hot like me or are working hard, it will get sweaty inside in temps over 50˚ when it's not raining. Since I tend to get really warm quickly when running I can't really say if the underarm laser-drilled holes helped, but considering most jackets in this weight class have no underarm ventilation I'll take it. It also has a cinchable hood and waist cord, making it really easy to seal up in windy weather. The cuffs aren't fully elastic but the non-elastic side has a longer fabric shield and it should improve breathability; even with small wrists I actually liked it more and never had an issue with it.

To be honest, I can't really think of much to improve for what it's designed for, they really put a lot of thought and design effort into this jacket. It's straight up the best ultralight jacket out there and will probably have a place in my pack for almost every mountain adventure! 

Notes: I have a size medium so it can be layered with a midweight puffy or fleece. I really like the blue color and the keeping the logo small is a nice touch.

PSA: Help the environment and fight climate change! Consider your requirements before every purchase and only buy what you need. Look at second-hand markets, repair what you have, and spend more if it means you'll be buying a product that lasts longer!

We want to acknowledge and thank the past, present, and future generations of all Native Nations and Indigenous Peoples whose ancestral lands we travel, explore, and play on. Always practice Leave No Trace ethics on your adventures and follow local regulations. Please explore responsibly!

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