Wool is fleece from sheep. Its crimpy fibers create millions of air pockets, making it a natural insulator. The long, exterior antistatic fibers repel water and soil while the shorter, interior fibers absorb moisture vapor up to 30% of the weight of wool before it feels damp. And wool retains 97% of its strength when it's wet!
Thinsulate insulation works by trapping air molecules between you and the outside. The more air a material traps in a given space, the greater its insulating value. Because the microfibers in Thinsulate insulation are far finer than other fibers, they trap more air in less space, which naturally makes it a better insulator. Thinsulate is breathable, moisture resistant, machine washable and dry cleanable.