Walker's Razor Series Electronic Earmuffs - The Razor Slim electronic ear muffs feature an ultra-low profile compact design. 2 Hi-Gain Omni Directional Microphones Full Dynamic Range HD Speakers For Clear Balanced Sound Low Noise / Frequency Tuned For Natural Sound Clarity Independent Volume Controls Sound Dampening Composite Housing Sound Activated Compression – 0.02 Second Reaction Time Audio Input Jack Recessed Volume Control Knobs Comfortable Headband W/Metal Wire Frame External Battery Door Operates On 2 ‘AAA’ Batteries – Included