Wool is a natural fibre, warm to touch; it has high thermal insulation properties (garments in wool are thicker and therefore trap a greater quantity of air inside) and it is temperature-regulating. Wool is therefore warm, soft, and improves breathability. At the same time it absorbs body moisture and guarantees excellent thermal insulation. Wool fibre is coated externally by scales and it has many elastic undulations, giving it its characteristic curly form. This structure gives it softness, elasticity and hygroscopic behaviour.

Wool pillows are excellent for providing insulation against the cold, but also for staying cool in summer. In fact, wool provides good breathability, regulating temperature during sleep. Wool fibres provide heat and insulation at low temperatures, but also ensure the cushion's breathability, therefore limiting sweating in summer.