There are musician and noise plugs to protect your hearing and swim plugs to keep water out.
Musician earplugs are custom made for comfort and have flat-response attenuators designed to reduce the loudness of sound without unduly distorting the sound.
Musicians perform in a variety of settings and can be exposed to quite high sound levels for extended periods. Protection is very important as research shows that sustained exposure to loud sound will lead to permanent hearing loss.
Noise plugs are solid or include attenuation filters depending on your requirements.
Swim plugs can be made to be floatable, with cords attaching them and in various colours.