The Aran Sweater has many attributes which made it suitable clothing for the island's community of fishermen and farmers. It is water repellent, not allowing the rain to penetrate the sweater thus keeping the wearer dry.
An Aran sweater can absorb 30% of its weight in water before feeling wet. The natural wool fiber used in the sweaters is breathable, drawing water vapor away from the skin and releasing it into the air, thus helping the body to maintain an ideal temperature.
Most importantly, of course, an Aran sweater kept the wearer warm on the cold days and nights at sea or on the farm. Wool has an excellent insulating capacity due to the high volume of air in it, and this helps protect the wearer from excessive cold and heat.