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  • Arc'teryx - Proton LT Insulated Jacket - Men's - Black

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  • Arc'teryx - Proton LT Insulated Jacket - Men's - Black

Arc'teryx Proton LT Insulated Jacket - Men's


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    4 Reviews


    Self-regulating warmth.

    You can rely on the Arc'teryx Men's Proton LT Insulated Jacket to keep you warm whether you're climbing a frozen waterfall or exploring the backcountry on skis. The advanced Fortius Air 40 shell fabric balances wind, weather, and thermal protection while remaining highly breathable to keep you comfortable over a wide range of temperatures, conditions, and activity levels. Coreloft Continuous 65 insulation traps and retains warmth, even in humid and wet conditions, making this jacket an ideal layering piece for winter activities. A high collar provides extra coverage in cold and windy conditions, while stretch-knit cuffs and an adjustable hem help seal out cold. With an articulated design and gusseted underarms, the Proton LT Insulated Jacket will keep you warm and moving comfortably throughout the season.

    • A jacket that delivers comfort over a wide range of conditions
    • Performance fabric balances breathability with water resistance
    • Coreloft Continuous 65 insulation traps and retains heat
    • Stretch-knit cuffs and adjustable hem help seal out cold
    • Trim fit allows this jacket to be worn as a softshell or midlayer
    • Arc'teryx specializes simple and functional designs
    • Item #ARC00KU

    Tech Specs

    Fortius Air 40 (92% nylon, 8% elastane), DWR treatment
    65g Coreloft Continuous
    Center Back Length
    29.1 in
    2 zippered hand, 1 zippered chest
    Claimed Weight
    12.9 oz
    Recommended Use
    alpine & expedition, climbing
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

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    Very Impressive Technical Jacket

    • Familiarity: I returned this product before using it
    • Fit: True to size
    • Size Bought: Small
    • Height: 5'11"
    • Weight: 140lbs

    Very comfortable, slim fitting, excellent ergonomics (as Arc'teryx usually does) and it does breath well as advertised. The face fabric seems impressively durable as well. I ended up wanting a hood and went with an Atom LT hoody as it met my needs better with the more wind resistant front and back face fabric, but for those looking for a jacket that provides warmth, some breathability and looks good doing it, definitely consider this.

    Protect, Breath, Layer or Don't Layer

    • Familiarity: I gave it as a gift but have feedback to share
    • Height: 5'10"
    • Weight: 146lbs

    The jacket is fantastic--if you're considering it even for a moment, pull the trigger on this one. Best performance, breathable yet protective (water/wind resistant---no it's not your Gore-Tex outershell) jacket, awesome to layer under a shell (check out the Alpha FL lightweight performance shell as a nice ultra-light outer layer to pair this with when the skies let loose) or use as a stand alone for hiking, backpacking and yes, you'll be tempted to show your outdoor style and throw it on for your casual cruisin. The small yet numerous design details had performance in mind, but the tempation to use it for everything will be hard to resist. I have numerous customers as well as friends and family who have this and swear by it.

    More Breathable Alternative to the Atom

    • Familiarity: I've put it through the wringer
    • Fit: True to size
    • Size Bought: M
    • Height: 5'9"
    • Weight: 150lbs

    I was looking for a piece that could function as a midlayer or outerlayer depending on the conditions and this was the ticket.

    The Proton LT has quickly become my Go-To for this exact use-case. I love it for resort days where my Cerium will be overkill. I also use it touring. I skin up with this as my outer layer and pop on my shell at the top. I opted with this over the Atom because it is a good bit more breathable. I would love it if it were just slightly lighter (warmth wise) but unzipping a bit has been all I needed to ensure I do not overheat.

    It is also great for cooler morning dog walks and wearing around town.

    As with all Arc'teryx, I purchased a Medium and it fits perfectly.

    Great stylish midlayer goes everywhere

      I've never worn the atom but lots of people tell me this is a new step up from that jacket. I was surprised by the warmth offered by such a thin insulated jacket. I throw it on to go do everything. If it's really cold I'll layer it with a shell (sidewinder for me). I really love the fitted cut because I'm tall and thin. Lots of jackets just fit like bags. I'm 6'3" 180 lbs and it fells like this jacket (large) was tailored for me.