Reviewed by: Second Wind Date Product Reviewed: 11/03/2011 Product Type: Gear icebreaker apparel icebreaker is a very unique company. They have taken a stance (a real stance – not a marketing ploy) on environmental conservation, from their materials, to their factories, every step of the way. Now, this isn’t done by throwing a couple bucks at Al Gore to offset a carbon footprint, instead, icebreaker took a holistic approach: from the raw materials, the farmers, the supply chain and transportation, to the manufacturers and their employees, icebreaker is striving (and doing an amazingly good job) to be in control every step of the way. Icebreaker is making a valiant effort to not only have a great slogan, “It’s about our relationship with nature and to each other”, but taking ground breaking steps in transparency all the way down to the end user on how they are living that slogan out (check out their ‘baacode’). LS Ace Zip First impressions upon unboxing: The top looks fantastic and I’m a big fan of the shoulder accent (and reflective piping) that is a bit of an Icebreaker trademark. As with most of their products, I found this top to be just as much at home sitting above a pair of designer blue jeans as it would sitting above a pair of sweaty running shorts. The cut is very detailed, the fit is just right, and it’s tapered to sit perfectly on your form while not being at all compressing. Icebreaker included a perfectly sized zipper pocket on the bottom right side(truly on the side – not on the front where it swings out and smacks back down on your waist each stride) that is small, thin, and tight so that whatever you put in it doesn’t jostle around. I thought the size of this pocket to be a really big deal – the size is perfect (I put an ipod and a key in that pocket with plenty of room and they fit in nice and tight and don’t bounce around). Additionally there is a cord hole at the top of the pocket (on the inside) to run your headphone cord up to the back of your neck where they included a loop to hold them in place on your run. I really like this up-the-back design and under the top – this keeps all the wires hidden and out of the way where you aren’t brushing them every stride or catching them with your hands. Icebreaker fashions, with no exaggeration, the softest, lightest, most comfortable apparel I have ever worn and this top is no exception. The LS Ace Zip is made of 97% Merino wool (not synthetic, pure, natural New Zealand Merino wool) and 3% Lycra. This thing has an amazing amount of stretch to it. Remember that even though ‘wool’ has a bad connotation with a lot of athletes and is known for being hot and scratchy, this Merino wool is like nothing I have ever felt. It breathes wonderfully, is weightless (I swear it floats with your body instead of lying on it), and, again, is the softest material I’ve ever felt (forget ‘wool’ – think 10,000 thread count Egyptian cotton and you might get some idea of what I’m talking about). Their Merino wool regulates body temperature so well that this is honestly a 3 season jacket (from early fall to late spring). I’ve worn it on days where the temperature reached 70 degrees and it was a pleasure, and this morning I wore it at 38 degrees and it kept my body just the right temperature. It’s nice to finally have something that works so well that you don’t have to layer different weight jackets. On the layering note, this shirt does work perfectly over a base-layer, however you can wear the LS Ace Zip with no undershirt and it feels great directly on your skin as well. One of my favorite things about Icebreaker apparel is that it is so effective at being naturally anti-microbial that it doesn’t stink. Ever. You can wear these tops in the heat, sweat enough that it changes colors from being drenched, throw it in the corner, pick it up the next morning and it smells WAG approved - but whenever you do decide to wash it, you just throw it in the washer. No fancy washing bags and delicate cycles, no dry cleaning, 100% machine washable and go. A+ product icebreaker, very well done.