The 3M™ E-A-Rsoft™ SuperFit™ Metal Detectable earplug is designed specifically for applications such as food processing, where detection of foreign objects is desired. This product features the proprietary SuperFit™ fitting ring to help insure proper fit, a stainless steel ball bearing implanted into the plug and a metal detectable cord. *The NRR may overestimate the hearing protection provided during typical use. 3M recommends reducing the NRR by 50% for estimating the amount of noise reduction provided.