It is the fourth and top layer of the K-Four multilayer compression bandaging system. It has a retention function, while also providing compression of up to 20mmHg on a 18–25cm circumference ankle. It can also be used to apply light pressure support to limbs in the management of sprains and strains, or during rehabilitation following orthopaedic surgery.
This a  water-resistant, vapour-permeable, knitted fabric consisting of cotton, acrylic and elastomeric fibres. The fabric is coated with particles of natural latex, which makes it cohesive and enables it to stick to itself. A type 3a bandage.