In 1962, Ray and Cecilia Benner developed a pliable silicone earplug. Foam plugs soon followed in 1972, invented by Ross Gardner.

Silicone is a common earplug material. They cost from three dollars to over a hundred and vary in consistency from soft, pliable masses to solid pieces contoured to the shape of the ear. Silicone blocks out sound and water.

Another common material is polyurethane and pvc foam. These are very effective at blocking out sound and are relative comfortable to wear. They must be squeezed tightly before inserting into the ear canal. They are also very inexpensive costing about a dollar or less for a pair.

Some cotton and wax earplugs are still sold today. They are comfortable but hard to keep clean.

There are even white noise earplugs available. These produce white noise inside the ear to cover up other sounds. These can be quite expensive at over one hundred dollars a pair. Available in cordless and earphone styles.

• Hearos
• Dream Essentials
• Howard Leight
• Mack's