Fleece is practical, durable, dries quickly, is light, really warm and also suitable for people with an allergy to wool.
There are many variations when it comes to fleece, including the thickness of the fabric and so on. Polartec® uses a measurement in grams per square metre: 100, 200 and 300. 100 is a summer fleece, 200 is a spring/autumn fleece and, logically, 300 is a winter fleece. If you opt for a blend of fleece and lycra, referred to as powerstretch, you will have a more fitted fleece. The so called high-loft fleece is ideal for very cold climates. Upright fleece fibres enable the air and also therefore the body heat to be retained very effectively, providing excellent insulation. The fit of these fleeces tends to be a bit looser.
Not every fleece is windproof. The Windstopper from Gore® and the Windbloc from Polartec® are both windproof thanks to the combination of fleece and a Windstopper-membrane. The downside, however, is that it is not as breathable as items without the membrane. Not everybody is warm enough with a fleece. Thermal underwear can always help.