Icebreaker GT 200 L/S Chase Zip

As a base layer, merino wool is truly exceptional. Icebreaker makes among the highest quality available, and the attention to detail is excellent. Though the price is also exceptionally high, I have zero regrets about purchasing and using Icebreaker in any serious outdoor pursuit. You can't make it stink!

Icebreaker next-to-skin underwear is really unlike any other product I've used; at my age and duration of active outdoor pursuits, that is a big statement. I've used every synthetic made since Lifa PolyPro, as well as silk and good old union suit cotton.

Merino Wool, and specifically Icebreaker's super-high end version, is easily the best comfort over a wide range of temperature/activity combinations, and uniquely will not smell up your car, your pack, or your girlfriend. That is not a small factor for many.  And for those of you for whom B.O. is not a consideration, well, we already know (trust me). 

The GT200 tech top (M's large tested) is the perfect piece for cooler weather cycling, skiing, and climbing. The zip is deep and although not particularly attractive when fully opened, goes well below the solar plexus allowing maximum direct venting/cooling.

The zip at the neck is a tricky bit of business that cheaper quality underwear usually gets wrong; this results in annoying, painful and distracting catching on beard stubble and unwanted rubbing in a sensitive area of the body. 

The overall fit is dreamlike, a perfect blend of stretch woven through the fine wool fibers.  Simple, flat-stitched thumb holes, neckline finish and zipper trim makes the lines clean and minimal.

The only possible downfall of this top of the line base layer piece is the top of the line price. Also important to keep it out of the electric dryer; if it does go in, the fit can be re-relaxed with another cycle and a hang dry. Once you start investing in Icebreaker or other high-end Merino pieces, you'll be vigilant on the laundry factor for sure.  And after just a few uses in the field, the price will be fully justified plus plus.