Pro 9 Noise Cancelling Hearing Protection provide the same protection as some of the most expensive electronic shooting ear defenders, and are more advanced than standard shooting ear plugs, using effective Noise Cancelling technology without batteries, electronics, valves, or any moving parts, the Pro 9 allows you to hear speech whilst cancelling out the damaging sounds! Unique patented sound chamber technology, directs damaging sounds away from the ear canal, where they are dampened, refracted and cancelled. The effect is amazingly clear low level sounds such as speech, but with highly efficient protection from damaging noise levels such as gunfire with over 32 Decibels of noise reduction, evenly across all frequencies.