Wool is perfect insulation for outdoors activies. We recommend it for insulation under your drysuit, insulation during your winter activites like skiing and nordic skating. Typical for these activites is that your activity is daylong and you would stop for a bite every few hours. Those stops are the moments when the effectiveness of your clothing counts. Where the woollies under some windproof and breathable thousers. Even without an outerlayer the wind is deflected by the dense material, and protects you. Humidity is transferred out and away from your skin.