Blackrock thermal insulated leggings are made from low density fibres which trap air next to the skin. An insulating layer is then created which protects you from the elements on chilly days. While a wicking layer removes moisture and sweat to prevent chilling. The fabric washes and dries quickly meaning it’s a highly practical workwear garment. There are no side seams, so you don’t need to worry about chafing or bulking.