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Women who love to challenge the elements will stay warm, dry, and oh-so-fresh wearing the I/O Bio Women’s Contact Long-Sleeve Zip-Top. This lightweight merino wool baselayer slides on smoothly, wicks away moisture to keep you cool, and naturally fights vicious odors. A touch of stretch creates a flexible, form-fitting shirt that’s perfect under a midweight climbing softshell or lightweight running jacket.

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Great Top

    The material is thin, but very warm. Maybe even a little too warm for spring. The top fits true to size and is extra long in the waist, which is good for tucking into bottoms. I wash it in a washing machine rather than by hand and air dry and it seems to be just fine. I am pretty gentle with it as I have some Patagonia woolies that ripped easily and don't want the same thing to happen.

    Softest merino baselayer i could find

      I spend a lot of time doing high output activities in the backcountry of the Canadian Rockies and had heard a lot about the "new" merino wool tops that are not itchy, breathable, warm, and stink-proof. I was willing to give it a try because all of my synthetic baselayers eventually need to be tossed due to stink. But i found that Icebreaker stuff was still too itchy to wear next to my skin. I had heard I/O Bio was softer and so took a chance on it. It is hard to believe it is wool! So soft and comfortable. Only had it for one month so far, but it has seen about 10 days of hard wear and tear. No stink. Love the thumb loops. fits snug, but not tight. Downsides: The fabric is very thin and i would worry about small holes developing over time.....we will see. Also, there is a very strange logo on the front that looks like a removable tag. I have had people try to remove it for me, thinking i had forgotten to take it off. weird!

      Way to go!

        I have a gear (and everyday) closet full of merino from many different brands. Therefore I was very surprised to get exited by this piece! VERY SOFT, and it seems very durable! I think this will hold shape perfectly and will take years of hard (ab)use without tearing.

        Besides the merino thing, this top have a fit that works for me; high -but not to high- collar, perfectly protected zipper, nice slim fit sleeve length, and the best;
        the thumbholes has moved on top of the wrist - not creating a cooling bridge directly on the veins!
        The jelly color is very rich and just like the picture!

        only wish is 1-2 inch longer body, but then thats always a problem for me (5,11)

        Not as great as Stoic merino

          For me, these shirts are just okay.

          For comparison, I'm 5'11" and the Stoic merino in a L fits me pretty well, it's a bit loose I had to get a L since the sleeves are long enough to make the thumb holes very comfortable.

          Pros: Performance is good. The fabric of the shirt, although thin, keeps me warm and dry and non-stenchy. I've worn this as a base skiing a few times and always been comfortable.

          Cons: Fit! The sleeves and length on this shirt are really short, and I like to pull my thumbs through the holes when I ski. On this shirt the thumb holes cut into my hands. It's uncomfortable enough that I can't wear them at all. The fabric on this top is also very sheer, enough so that you have to be careful what you wear under it if you're wearing it alone after skiing, although it's still warm.

          Bottom Line: If you're not an amazon this shirt will probably work great for you! taller girls, go for Stoic.

          I/O Bio Merio Long-Sleeve Zip Top

            This jersey is not 100% merino wool as stated in the tech specs and it is kind of see through. Overall it is okay!

            How Lovely

              I'm 5'4, a muscly, strong upper-body 130lbs, and the medium fits great! I love the thumb holes! It's not terribly thick, but it's perfect for a base layer and sexy as an around-town top, with great length that elongates. I was afraid the light blue print would be too busy, but it's not at all. I would highly recommend this top!

              Real Comfortable!

                I like the top and matching bottoms. They are real comfortable and kept me very dry and are perfect for layering. I wore the set all week skiing in Colorado in February. It is even great for after ski wear. I can see myself wearing these for other activities as well.

                io for all

                  An amazing layer or stand alone zip top piece- I am 5'8 and medium athletic build- and the Medium is the perfect size. I wear this day after day as my baselayer skiing and ski touring, as well as a nice top to run around in for hiking and climbing and social activities. It wicks moisture extremely well, deters odor magnficently (i've put it to the test!), and is soft and comfortable with great ease of movement. Excellent feminine cut as well.

                  Merino, it's what's for ... everything

                    Got the IO grid color and love it. The Australian merino wool rivals the New Zealand wool. Feels extremely soft, absolutely not itchy. The IO grid color is really awesome. It feels very refreshing to see another company to produce high quality merino garments while adding some pizazz to it (Mission Playground is another company that makes patterned wool undies, and even old Patagonia has added stripes to the wool tops this year). Be sure to order a size larger if you plan to layer it on top of another wool underwear. I usually wear xs or sm in Pati sizes, but I got the medium for this top and it fits very well. I wear it on top of another thin wool l/s, and it looks very presentable that I can wear it outside.