Shower cap

A shower cap is a cap worn while showering or bathing, to protect hair from becoming wet. Alternatively, shower caps for children can be crowns with wide brims that prevent water and shampoo from getting in the eyes while allowing the hair to be washed.
Many are produced by joining two layers of fabric together in order to make the shower cap not only waterproof but aesthetic also. However, simpler ones are purely made from one layer of a waterproof material, often plastic. They all contain an elastic band to contain the user's hair.
 

disposable shower cap