The external auditory meatus (EAM) is also known as external acoustic meatus or ear canal. This is the pathway from the outer ear to the middle ear or from the outside of the head to the eardrum membrane. The average adult EAM is about an inch long and 0.3 inches in diameter. It is a curved tube and the outer part is made up of cartilage while the inner part is made up of bone. The tiny hairs in the ear canal and its sweat glands which particularly produce ear wax are helpful in protecting the inner parts from foreign objects.