Proplugs are designed to be non-invasive and are inexpensive, long-lasting, and ready-to-wear. Plus, they can be quickly and easily fitted. Proplugs are made of soft, hypo-allergenic Kraton with memory that provides a watertight seal. Since 1977, when Proplugs were first created, the patented design has been recognized by professionals and patients alike as having the most features in respect to comfort and protection. Compare Proplugs to any other earplug and you'll see why it's the only one to use.