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Wool underwear? No, we’re not kidding. The I/O Bio Women's Contact 1 Boy Brief’s silky-smooth Enigma knit caresses your nether-regions with never-itchy, naturally anti-odor, and super-soft merino wool. A touch of elastane ensures that it doesn’t sag or bag, and the wide elastic waistband stays put without digging. Out on the trail, skiing the steeps, or every day, these boy-cut undies offer killer comfort.

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A lil' different from the Icebreaker one

    I found these on crazy sale so I figured that maybe they are like the Icebreaker Sprite Hot Pants (which I love) since they look almost exactly alike and went for it. I got the size S. The main noticeable difference is that the leg openings on these bottoms are a little tight, but they aren't too constricting so its still wearable. I have muscle-y thighs, which I've noticed can be an issue when getting boy shorts-type underwear, but I don't have this problem at all with the Icebreaker ones.

    Not for me, but pretty nice

      I have fuller thighs and found these to bind at the leg openings, it wasn't so bad that I couldn't stand it but I didn't want to chance getting chaffing in a sensitive area. Other than that they were a great fit in every other way. I really love the I/O sport bras and wished I could have kept these undies to have a matching set, but oh well.

      Once you go Merino you will never go back

        I have never cared much about what I wear in terms of underwear on a ski day. Lace to cotton, thong to grannies I have warn it all in the backcountry, however now that I have gone Merino I will never go back! These are not only soft, but they keep EVERYTHING nice and dry and the cut is super comfy so you aren't left trying to adjust yourself when you should be dropping that line. If you are looking to treat yourself to something really great, you want to treat yourself to some I/O BIO briefs!


          Very soft to the touch, the wool couldn't be softer, not itchy at all. Wears and washes well. and they look cute too. would buy more in different colors, cause i keep reaching for them not only for sports. great product.

          Can anyone comment on the rise? They look...

          Can anyone comment on the rise? They look like low rise in the pics. I'm looking for something with a medium rise.

          I would definitely say mid-rise. The newest ones are about an inch lower in the rise than the prior generation, but still mid. The cool part is that they are made of stretchy merino so you have a little more wiggle room as far as rise anyhow...

          The past two seasons brief is lowrise.. Loved the old fit! I have a big but, and these will not really stay put, I have to pull up to often... but as I said, I have a big but (108cm seat 78cm waist). If your but is more average you should be better than fine whit these! Despite the 'update' of these, they are still my absolute favorite.

          i guess it depends on your definition of *low* and *mid* rise and your unique body. i am 5'10" and 130lbs. i bought the size small in these and they fit perfect. the waistband sits at 3 1/2" below my navel. i get full coverage in the back thanks to the wide waistband. super cute, super comfy whether you call them low or mid rise...