The Moldex Battleplugs are a new type of reusable earplug. These patented, baffled hearing protection devices have two modes which provide completely different noise reduction ratings. A small hinge on the outside part of the earplug allows a cap to be either open or closed depending on the expected noise level. If the caps are closed, the Battleplugs have a noise reduction rating (NRR) of 24. In the open position, they have an NRR of 9. When the caps are open, the wearer is still protected against loud blasts, but they are better able to hear commands or noises from the surrounding area. Blast protection data shows that in the open position, the louder the blast, the more noise reduction. When there is going to be continuous and steady noise or sustained firing, the closed position provides maximum protection. Opening and closing the cap may take you a couple of tries to get down, but the learning curve is definitely short. Within an hour of wearing them, I was easily switching between positions without jarring the plugs loose from their snug spot in my ears. The shape of these earplugs and their soft flexible construction make them comfortable for long-term wear. While they aren't as lightweight as the standard, and very popular, Moldex Pura-Fit 6800 Foam Earplugs they still fit well and can be left in and forgotten about for a long time without developing sensitivity. The Battleplugs are also washable and reusable. Wash with soap and water and dry thoroughly. When cleaning it's a good idea to check for tears or damage. A damaged plug may not provide the protection you think you are getting, and you may put your hearing at risk. These convertible plugs come with a cord to attach and keep track of the earplugs while keeping them handy as well as a small clam shell case for storage when they are not in use.