The Black Diamond Women’s Coefficient LT Hybrid Hoody fills a sweet spot between fleece and light insulation. Designed for high-output mountain days, this piece blends breathable grid fleece with light synthetic insulation across the chest to add warmth where you need it most. After wearing it for trail runs, chilly hikes, and breezy bike rides, it has quickly become one of those layers I reach for when the weather sits right at the tricky in-between zone.
I can easily say that this layer has become my new favorite, which means I have put it through the test in various activities this spring and I am happy to now call it an essential to my outdoor wardrobe!
Coefficient LT Hybrid Hoody Core Features
- Polartec Power Grid fleece for breathability and moisture management
- Light synthetic insulated woven front panel for added core warmth
- Slim, athletic fit designed for layering
- Under-helmet hood
- Guessested underarms for mobility
- Thumb loops for added coverage
- Zippered chest pocket
- Weight: 205g
- MSRP: $229
A hybrid layer that makes sense
The hybrid construction is the defining feature of the Coefficient LT. The body and sleeves use a Polartec Power Grid fleece, which is known for it’s warmth-to-weight ratio and it’s ability to breathe well during high-output activities. The gridded interior traps warmth while still allowing heat and moisture to escape when you’re working hard.
Across the front of this hoody, Black Diamond adds a light insulated woven panel that helps block wind and adds a little extra warmth for your core. This simple design makes a noticeable difference when in cool and breezy conditions.
The result of these design aspects is a layer that feels warmer than a similarly lightweight fleece but breathes much better than most insulated jackets. This piece has kept me feeling warm when I have needed a light layer, and allowed me to keep moving at a strong pace without overheating and sweating through the fleece.

Built for high output (or not)
This piece really shines during activities where you’re consistently generating heat. This piece is designed so that the fleece panels dump excess warmth, preventing the excessive trapped heat that can often happen while wearing a fleece during an activity.
I have loved this hoody for cooler walks and runs when I have just needed that thin extra layer to keep me from being too chilled. I have stuffed this piece in my hip pack to throw on for bike descents and breaks while mountain and gravel biking. I have layered this piece under a puffy and a shell (personally, I love a thin fleece like this that you can easily wear under a warmer layer). The Coefficient hoody pairs perfectly with Black Diamonds other pieces – see it here under the Deploy 3L:

Fit and Comfort
This hoody has a slim and athletic feel. I tend to like my active wear snug but not too tight – this hoody has found a good balance in trim, not too tight and not baggy either. As mentioned above, the slim fit and the light fabric make this hoody perfect for layering, it fits perfectly under a shell or puffy. The stretch in the fleece fabric allow for excellent mobility, the gusseted underarms make reaching overhead seemless – I am happy to run and scramble in a piece like this. I got a size medium for this hoody and the fit was perfect.

The hood on the Coefficient is designed to fit under a helmet, which works great for biking and I am sure I will love it once ski season rolls around. And even without a helmet this hood provides a close and comfortable fit that can add a little extra warmth to your head and neck when you need it.
Small details like the thumb loops and zipper chest pocked make this piece easy to wear and truly functional.

The Black Diamond Coefficient LT Hoody is a thoughtfully designed layer that excelled when put to the test this spring. The combination breathable grid fleece with targeted insulation offers a balanced experience of mobility, warmth, and ventilation.
Buy now: Black Diamond Coefficient Hybrid Hoody
The Bottom Line
Midlayer Perfection
The Black Diamond Women’s Coefficient Hybrid Hoody is a versatile mid layer that finds the balance between warmth, mobility, and breathability. The combo of fleece and synthetic insulation keeps your core warm and lets you shed heat when you’re working hard. Whether you’re biking, climbing, running, or hiking, this is an excellent midlayer that you will continue to reach for again and again.
The Good:
- Lightweight
- Excellent Mobility
- Warm yet breathable
- Stylish and comfortable fit
The Bad:
- Premium cost
- Limited pocket space
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Mobility
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Breathability
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Comfort
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Fit
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Value
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Versatility
