A nyone else stop to de-layer 10 minutes into every hike? I truly cannot remember a time that I’ve actually worn my down jacket during an entire hike or day backpacking without feeling uncomfortably hot and sweaty. It’s so difficult to find layers that simultaneously keep you warm without overheating while engaging in high-output activities. This winter, I’ve been testing the Sierra Designs Borrego Hybrid Jacket as a lighter insulated layer for a wide range of activities.

With a soft-shell design on the arms, shoulders, and hood, this is a thin and low-profile layer. However, there are also two large panels of micro-insulation across the entire back and down the center from the chest. This provides warmth where you need it most: your core. It almost feels like wearing a thin long sleeve layer with a lightweight insulated vest over it. Warmth where you need it, and minimal breathable design where you don’t.

On an early morning run in Little Cottonwood Canyon to a popular ice climbing spot.

I’ve used the Sierra Designs Borrego Jacket for a variety of activities this winter in Salt Lake City. I’ve used it as an outer layer on warmer hikes, a base layer for extremely cold backcountry skiing, and an extra emergency layer for trail runs and summit hikes. Unfortunately, most of these endeavors have been solo so most pretty much all of my photos are necessarily selfies.

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The soft-shell arms do a really nice job of repelling light precipitation. I hate bringing a full shell jacket for a 30% chance of rain.

I am SO happy I had this jacket in my pack this day. It was about 15 degrees, and it was an emergency layer in case there was wind on the summit I was tagging. Which there was. This was the best selfie I could muster before sloshing back down through snow.

Honestly, I’ve found a use for this jacket for pretty much every activity I’ve done this weekend. My two favorite uses so far have been as an outer layer for extremely cold trail running, and as a base layer for backcountry skiing. For both of these sports, I have a hard time finding a layer for this scenario that is warm enough yet also breathable. I’m also excited to have this in my pack as a summit layer for summer activities, as opposed to a down jacket which usually seems too warm.

Clearly working through a very cold day. This jacket has been perfect for high-output activities in extreme cold. The micro insulation is warmer than typical base layers, but it’s not as heavy/stuffy as a full synthetic or down jacket.

The body of the jacket fits me perfectly, but the arms are a bit too short for the thumbholes to fit comfortably

This jacket can serve a different purpose in every season.

Though this isn’t the highest warmth-to-weight jacket on the market, I absolutely love having it in my upper layer lineup. I am most impressed with its ability to keep me warm without overheating during high output activities in the winter. The thin sleeves combined with micro-insulation keep your core warm without excessively sweating everywhere on your body. I most likely wouldn’t choose this jacket for backpacking trips where weight and warmth are the highest priorities. However, I’m very excited to use it this summer as a summit and descending layer. For $130, it’s a great deal for anyone looking to add some versatility to their layering system.

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The Sierra Designs Borrego jacket was donated for purpose of review.

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Hi! My name is Katie (Gallon Smash) Kommer. I recently completed the John Muir Trail, and am already hungering to find my way back to my truest, stinkiest self. On the trail, I'm known as gallon smash for my exceptional ability to fall headfirst into a bush or a river, and in the "real world" I'm known as the recent grad who's trying her best, okay?