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Ditch your old, heavy midweight layers and reach for the warm Men's Rho AR Zip-Neck Top. Arc'teryx used Polartec's Power Stretch fabric in order to give you all the warmth you need from a cold-weather layer and all the flexibility required for alpine climbing, trail running, or backcountry skiing.

  • Polartec Power Stretch fabric has a flexible construction that moves with you so achieving full range of motion is never a problem
  • Widweight Polartec Power Stretch fabric offers a supreme warmth-to-weight ratio to help you layer effectively in the cold
  • Polartec Power Stretch fabric dries quickly and allows for moisture and heat to move away from your skin
  • Trim fit keeps this top close to your body so there's no excess fabric to get in your way when you're moving or when you pull a layer on over the Rho
  • Low-profile laminated chest pocket and laminated zipper won't get in the way of layers on top
  • Collar zipper allows for easy venting and makes it easy to pull this top on and off

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Here's what others have to say...


Wish I had one for every day!

  • Familiarity:I've used it several times
  • Fit:True to size
  • Height: 5'6"
    Weight: 155 lbs
    Size Purchased: small

This product work really well as a base layer or as a mid layer. It even works great on its own. It is very soft and warm and it layers really well. I am 5'6" and I have a small. Medium probably would work well for me to.


My third one

  • Familiarity:I've put it through the wringer
  • Fit:Runs small
  • Height: 5'8"
    Weight: 150 lbs
    Size Purchased: Medium

What more needs to be said. I live in a 100 year old house in Montana. This is my standard wear from October to April. I'm out on dog walks 4 times a day, no matter what and the Rho and a shell or the Rho and a puffy are all I ever need.

I've tried a bunch of Power Stretch tops and the Rho's version is the perfect blend of fuzziness, stretch, and weight (every company seems to get a custom version of Power Stretch).

Unanswered Question

hi, my chest is 44 inches, what size would you recommend for this? I dont live in the US so ordering one and returning it if doesnt fit is not an option. By the way, I wear Large for almost everything. thanks!


i love wearing this thing

  • Familiarity:I've put it through the wringer
  • Fit:True to size

i bought this mainly to wear casually outdoors around my home in michigan in the winter. i have used other base layer shirts in the past but this is the only one i wear now. its very comfortable and very warm. on an average 20 degree fahrenheit day with a bit of wind and in combination with my atom sv hooded jacket i stay pretty comfortable. if you're out hauling wood or doing sustained work in these conditions you may get too hot but you can always just unzip your jacket a bit. i just love this thing, it has finally made my michigan winters bearable becuase i dont like sitting inside all day but hated freezing outside. i also use it on my many vacations out hiking the parks and it is very comfortable to sleep in inside my sleeping bag.


The WARMEST base layer!

  • Familiarity:I've put it through the wringer
  • Fit:True to size

Fit is amazing. Warmer than any other base layer I have tried. It has held up well to the abuse of bc skiing and climbing. Unless its arctic cold, i will only wear this and a shell.


Great base and/or mid-layer

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

I bought the Rho AR a couple of years ago and have been using it for a mid-layer under my shell while skiing, as well as my primary outerwear as I'm out in town with the wife and kids. I recently bought another Rho AR so I wouldn't be suffering while the other one was being washed. Great product. Very warm and breathable. Good odor resistance, too. I'm 5'11", 170 lbs., and a medium fits me perfectly.


Very warm base layer

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

This was exactly what I was looking for to go with my Cap 4 bottoms on super cold days. I got to use it this weekend sailing in low 40's, and until the temps dropped into the 30's I was good with just this under my shell. Its trim fitting, but definitely thick so it takes up room. Can't say enough about how quickly it traps wamth.



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

I knew this pullover was going to be worth the money. The construction and design that went into this zip-up is exceptional. Arc'teryx pays amazing attention to detail. I purchased the small and it fits perfect on me. I am about 6' 0" 160lbs for your reference. I will definitely purchase another color in the near future.

you fit in a size small?? Did it fit like an under armour base layer?

6 feet and 160 lbs and you go for a small? Thanks for the info. I'm taking my chances and go for a small too! No product returns for me as I'm way outside the US. Question, what is your chest size?

I'm 5'9 160 lbs, chest 38-39" waist 32".

I've tried the previous Rho AR from a...

I've tried the previous Rho AR from a friend and the Medium was perfect. I'm usually a small in every single other top I've had. Should I stick to the Medium for the revised cut?

Yeah. The sizing is still runs a bit small with the new cut so size up. I'm a small with everything, but medium in the Rho AR top.

Hey Jimmy. I would like to know your chest size and height. I'm struggling between a small / medium.


just a winner of a top

    yep I am diggin the the super stretchy in all directions newly cut RHO AR. Correct me if I am wrong...this version seems a bit less boxy and more comforming than the previous addition that had been around forever. I am 5'11 165lbs and 33"waist. My sleeve length when buying dress shirts is 35" and a 16" neck is a touch big but comfy. This AR in a medium is perfect. Super soft feel. Great for colder days on the hill as a base layer