Abstract: A device to be worn by a person such as an athlete to protect the knee from external objects and to afford strength for the knee joint.It comprises a thigh member and a calf member as well as a pair of arms extending from each of such members toward the knee joint and on opposite sides of the knee. Each adjacent pair of arms is connected together by a hub member which extends through an opening in one arm and is fastened to the other arm. A washer is mounted between the arms and is formed with an abutment to be engaged by a limit-stop on one of the arms.The thigh and calf members each comprises a pliable member as well as a flexible cellular material. The cellular material is provided with a tab which extends through a slot in the pliable material such that as the pliable material is firmly attached to the wearer, the tabs can be pulled to straighten the cellular material against the leg. This prevents gathering of the cellular material and also permits of adjustment for varying leg sizes.