Shaft skin
Shaft skin is the skin which covers and protects the parts of the penis shaft. The shaft skin is part of the epithelium of the penis. The shaft skin incorporates a layer of muscle fiber called the Dartos.
The Dartos is not attached to the underlying Buck's fascia, so there is a very high degree of mobility, allowing gliding action.
In humans and some other mammals parts of the shaft skin become covered with pubic hair at puberty.
Note: The foreskin is not part of the penile shaft skin but a separate "organ" which covers and protects the glans penis. The shaft skin, the foreskin and the preputial mucosa build the epithelium of the penis. The outer layer of the foreskin is similar to the shaft skin.