The merino wool the 200 Oasis base layer leggings from icebreaker are crafted from is as high-tech as any other synthetic material. The natural and sustainably sourced fabric regulates your temperature, doesn't itch, wicks moisture, and is odour resistant – yes, for days. The 200 weighting denotes that the pair is designed for warm to cool climates, delivering complete comfort no matter the activity. Merino.