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  • Under Armour - Base 4.0 Bottom - Men's - Black/School Bus
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  • Under Armour - Base 4.0 Bottom - Men's - Black/School Bus

Under Armour Base 4.0 Bottom - Men's

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    • Black/School Bus

    5 Reviews


    The wait for first chair sometimes makes you shiver, but when it threatens to dangerously lower your body temperature, slip on the heavyweight Under Armour Base 4.0 Bottom. It's Under Armour's warmest baselayer pant for the days that separate the care-free skiers from wussy hot-cocoa drinkers.

    • Heavyweight, four-way stretch polyester and elastane fabric maximizes heat retention, breathes away moisture, and dries quickly if you take a hike in the afternoon
    • Flatlock seams and ergonomically placed seams let you move naturally while skiing or boarding without chafing
    • Elastic waistband secures the boxer as you get gnarly on or off the hill
    • Working fly simplifies pee breaks
    • Armour Block anti-odor technology in the fabric inhibits the growth of odor-causing microbes
    • Item #UND0479

    Tech Specs

    96% polyester, 4% elastane
    Insulation Weight
    Recommended Use
    heavyweight baselayer, sub-zero days, skiing, snowboarding, winter sports
    Manufacturer Warranty
    limited lifetime

    Tech Specs

    • Reviews
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    Favorite Base Layer!

    • Familiarity: I've used it several times
    • Fit: True to size
    • Size Bought: Medium

    Love this base layer. Very comfortable. Not too tight around the goods and very warm. Wore a shell over and not cold at all in 12 degree ski weather! Highly recommend.

    You call this winter?

    • Familiarity: I've used it several times
    • Fit: True to size
    • Size Bought: Large

    I purchased these to wear during my son's 24 hour winter campout for scouts. They kept me warm the entire time with only a pair of military utility pants on over them. Ihave no doubt that if it dipped near zero I would have continued to stay comfortable by simply putting a pair of snow pants over them. They are by far the warmest, most comfortable, base layers I have ever worn.

    The warmest baselayer ever!

    • Size Bought: Large

    These are by far the warmest baselayers I have ever seen. I love them for skiing. I wore 2 base layer bottoms for years, but these finally keep me very warm all alone. I like to be warmer than most people, and these work perfectly for me.

    Fits Small

    • Familiarity: I've used it several times
    • Fit: Runs small

    I love these base layers for very cold days, but they fit very small, the large says [34 - 36in waist] ... I am a 32-33 inch waist depending on the pants (bought large so that they would fit somewhat loose) ... and the large is too tight

    Thick and burly

    • Familiarity: I've used it once or twice and have initial impressions
    • Fit: True to size

    I have used mid-weight legging similar to the UA 2.0 before but I entered a new world when I tried out the UA4.0 recently. These heavyweight bottoms are not ideal for activities as heat-producing as trail running, but they will keep every bit of your lower body warm during other activities where your body needs a little extra help. Still maintaining a low fitted profile and the elastic feel of thinner tights, the 4.0 will not drop the ball when you are buried in spindrift.