Plugs are the cheapest form of hearing protection, and usually have around 30dB of noise reduction. This is the most popular form of hearing protection in the work place, however, they only work if you insert them properly. You must roll the foam in between your finger tips and insert gently into the ear canal, holding until the foam expands to the shape of your ear canal. For extra protection, as well as to ensure noise is being properly reduced, use this form of hearing protection as well as ear muffs over top. Ear plugs should be replaced and discarded after each use.