Walker's Razor Slim Low Profile Electronic Ear Muffs protect your hearing with a 23 dB NRR while allowing you to hear commands and communicate using SAC technology that reacts in 0.02 seconds. Low-profile ear cups, hi-gain microphones, and volume control provide natural sound clarity, while the durable, rubberized composite housing ensures long-lasting performance. These muffs include an audio input jack and 2 AAA batteries for immediate use. Noise Reduction Rating 23 dB Sound Activated Compression 0.02 seconds Ultra low profile ear cups Audio input jack for external devices Two hi-gain omnidirectional microphones Volume control for natural sound clarity Rubberized, sound-dampening composite housing Includes 2 AAA batteries, external battery door