These waterproof ear plugs are soft and made of antibacterial safety silicone. They fits the ears outline comfortably and are very good for swimming. Ergonomic left and right ear symmetrical design to prevent otitis media. Very thin – less than 0.1mm and will protect the eardrum. Hollow handle design to allow for sound clear conduction. Great drainage effect to prevent tinnitus. No need to worry about mold.