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Arcteryx Phase SL Boxer (Winter 20)
    Arcteryx Phase SL Boxer (Winter 20)
    Purchase Arcteryx Phase SL Boxer (Winter 20)
    • Arcteryx Phase SL Boxer (Winter 20)

    • £30.00 (RRP:£40.00, Save 25%)

    • Option:

    • Delivery: Free UK Delivery on all orders over £30
      Order by 2pm for same day dispatch (M-F).
      Full UK and International Delivery details.
    • Returns: 60 Day returns
      Return unwanted goods within 60 day
      For more info see our full Returns Policy
    • Customer Rewards:
      You'll earn a Facewest Credit of £1.50 with this item. Details here.


    The Arcteryx Phase SL Boxers are light and comfortable underwear ideally suited to intense activities. They are constructed from Phasic SL fabric, which is the lightest of the Phasic fabrics. This ensures absolute optimal wicking properties and is ideal for high aerobic stop-start activities. Manufactured using flatlock seams and a soft waistband, so you are ensured comfort with no chafing.

    Phasic Fabric


    Phasic base layer fabric is compiled from two different yarns. The first is a non absorbent hydrophobic yarn, which will shed water molecules pushing them onto the PHi yarn. Silver ions are encapsulated into the hydrophobic fibres of the yarn, which provide anti-microbial properties to help eliminate odour.

    The second yarn is PHi, a multi dimensional yarn which wicks moisture laterally along the length of the yarn, effectively dispersing moisture evenly across the garment. Temperature regulation is improved as this dispersal eliminates cold spots. As you slow down or stop the fabric will dry quickly, as a result of the larger surface area the moisture is covering. This quick evaporation helps to retain body heat.

    Arcteryx Phase SL Boxer Features

    • 100% Phasic SL polyester fabric
    • Flatlock construction
    • Gusseted crotch
    • Durable Anti Odour finish
    Next to skin

    Size Guide

    Arc'Teryx Men's Trousers

    Your Body Measurements in Inches:

    Size Waist Hip Inseam
    Small 32" 37.5" 32"
    Medium 34" 39.5" 32.5"
    Large 37" 42.5" 33"
    XL 40" 45.5" 33"

    Customer Reviews of Arcteryx Phase SL Boxer (Winter 20)

    Arcteryx Phase SL Boxer Review
    Verified Buyer
    Athens, Greece

    I am a big fan of the fabric used in these boxers and have quite a few base layers of the same fabric. It is really leightweight has a silky feeling, retains its stretch, does not retain odours. Overall a great baselayer.

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    Arcteryx Phase SL Boxer Review
    Verified Buyer
    Hebden Bridge
    A great pair of knickers but as a man who is used to boxers it takes some getting used to the tighter fit. Still the wife finds them comedic and they wick beautifully. Damm pricey for a pair of knickers but may save chaffing thighs.FYI, used one weekend in the Lakes and one cycle ride in Pennines
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    Arcteryx Phase SL Boxer Review
    Verified Buyer
    Blandford Forum

    Arc'teryx seem to make the best kit out there for any outdoor adventure in my opinion! These boxers are not only comfortable; but they are long enough to ensure they don't ride up your leg even when making challenging moves whilst mountaineering. I've just come back from a weekend of climbing/bouldering and compared to the Rab pair I wore the previous day, these are by far the most comfortable. I have a 32 waist and found that the medium pair give a great fit

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    Arcteryx Phase SL Boxer Review
    Verified Buyer

    I have bought a pair of these in size XL when they were on sale. I would say they run a little bit large, but nothing to worry about. The pair I got had a small hole just below the waist band, looks like a damage from pulling it too hard, that's why I give it only 4 stars. Otherwise the material is breathing well and soft, making for a comfortable pair of boxers.

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    Arcteryx Phase SL Boxer Review
    Verified Buyer

    Finally secome to sports pants after suffering every time I'm out with cotton boxers. I had the attitude that there not important as there underneath, but are always wet with sweat and never fully dry under trousers or shorts.

    I bought these because I'm an arcteryx convert and These for once were not a lot more than the competition.

    The fit is excellent cupping me like the hands of Kelly Brooke and they wick like nothing I've ever known! After a hard ride on mtb trails my pants are usually wet with ether rain/ puddle water or my own sweat and have to do the super quick change in the car boot without being arrested. I've had a dozen outings in the phase sl boxers now and in mixed weather and there always dry and comfy.

    In short worth the cash! And will buy another pair shortly and the phase base layer.

    Thanks facewest

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    Arcteryx Phase SL Boxer Review
    Verified Buyer
    Rumney, Cardiff

    I have been wearing a pair of rab meco boxer shorts for 3 years or so, but decided to purchase another pair of boxer shorts, so I did a bit of research and all the fingers pointed at the arcteryx sl, so I purchased them, I field tested them last weekend doing the horseshoe in the beacons in -16 and 70mph winds, while my brother kept on holding his private parts, I was toastie and so comfortable -you forget you're wearing them. I can highly recommend them, and once again a very keen price from facewest and a speedy delivery

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    Arcteryx Phase SL Boxer Review
    Verified Buyer

    I recently bought these to take away for a 10 day backpacking trip and over the course of 10 days walking I've been pleased with their performance. Over the years I must have tried a wide variety of boxer short base layers from other manufacturers in the quest to find something that fits well and is comfortable whilst still being breathable.Whilst merino boxers are comfortable for sleeping, relaxing etc I just don't find them comfortable for all day use and so have tended to go for the synthetic ones and wash them as I go.Whilst these shorts are not perfect, they're certainly the best ones I've found and used to date.The breathability and comfort of the fabric is excellent, the only issue for me being that the fit is just not quite 100%.Comfortable for extended use when walking, they did the job well.Very quick drying once washed. Recommended.

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    Arcteryx Phase SL Boxer Review
    Verified Buyer
    Saffron Walden, Essex

    I bought these to wear under a compression layer when skiing, as I wanted something lightweight and breathable, and most importantly wrinkle free.I have a 32 waist and have tried the Small and Medium sizes.The Small size provides the best wrinkle free fit, but the Medium is not excessively baggy either.They do not stretch excessively during the day, wash easily and dry fast, which is just what I was looking for.As commented the packaging is excessive for sports underwear, maybe Arcteryx are trying to justify the relatively high price.Recommended.

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