The Icelandic wool has both very long hair, which are thick and rough, and short hair, which are soft and thin. These two types of fibres are: inner fibres, which are soft, fine and highly insulating and outer fibres, which are long, glossy and water-repellent. This fibre combination increases the air in a wad of wool improving its ability to absorb vibration. We then use a soft felting technique making sure that these properties are not lost by densifying the material too much.