A breakthrough is hearing protection, ZEM lets you hear what you need to hear, but protects you from what you don’t --- without fancy electronics. ZEM technology is the product of years of research and development by a renowned authority in auditory research --- Dr. Jozef Zwislocki, distinguished Professor Emeritus at Syracuse University. ZEM patented technology uses sound energy in combination with lightweight, airtight chambers to divert sound from the sensitive ear anatomy. The ZEM technology reduces sound evenly across all frequencies so that speech is not distorted. Capable of suppressing harmful sounds up to an incredible 31dB, this enhanced model is perfect for indoor ranges and other enclosed environments. Includes four replacement cuffs. Available in black or olive drab with gold “NRA” imprint. One size fits all. Made in USA.