Walker Razor Behind The Neck Hearing Protection Ear Buds with Sound Amplification and Compression Behind-the-neck design doesn't interfere with your weapon, allowing for complete target focus. Non intrusive design is perfect for all applications where hearing protection and environment awareness is critical Hi-Gain directional microphones amplify external sounds for increased environment awareness Sound Activated Compression circuit (SAC) provides a no-fail system for protecting your ears from harmful muzzle blast Powered by rechargeable LIPO battery 250mAH battery for 10 hours of use 31dB NRR Flexible design makes it easy to carry and store Designed and Engineered in the USA