According to different functions is recommended to use the knee of two climbers. One is the kind of outdoor shop more common thick knee (Figure 2) indeed, in front of a big hole to expose the knee, usually bundled, and then gluing a fixed knee. Fasten knee after this can not easily bend the knee, thigh, knee and lower leg is always a straight line, therefore, very suitable for severe knee injury after the "brake", and because of the airtight nature of their material is also difficult for daily on the knee protection. The other is a thin set of knee pads on his knees, a certain degree of flexibility, belt, the knee still be able to free activities, but can obviously feel the patella was gently tightened a bit, this slight braking knee can be used for normal movement of the knee protection, and that the knee is very good ventilation, usually with a basic will not feel any inconvenience, it is proposed that each of the mountaineering activities, use this light system move the knee.