Bluetooth sync with mobile devices. This set contains Walker's Razor Slim Quad Electronic Earmuffs with Ultra Low Profile Ear Cups (Flat Dark Earth), 2 x Aaa Batteries, Limited 1-Year Warranty, Walker's Razor Tactical and Hunting Walkie Talkie Attachment, Walker's Crosshair Sport Shooting Glasses (Clear), and Top Brand High Quality Microfiber Cleaning Cloth.