HARMONICA knee pads item no. 13v (long)

The outer cover and bellows are made of rubber-like plastic and are therefore an inexpensive alternative to No. 13, but are not resistant to chemicals.
This patented knee pad goes with your movement. The elastic folds adapt to the knee joint in any position and when walking. The pad is replaceable and by placing the buttons in the lower area, the strap does not go through the back of the knee.