30 Sets of Headphones,each bulk headphone individually sealed. Designed with Adjustable headband, comfort and lightness,ideal for classroom use and school testing. Extra Soft Leatherette Ear Cushions; Ear Cushions Can Be Wiped Clean,Provide you with stereo audio clarity and nice sound quality. Stereo 3.5 MM Plug and 4ft Cord Works with Smartphones, Chromebooks, Tablets, Laptops, Computers, Fitness and Audio Equipment. These headphones can be widely applied for classrooms, school, libraries, museums, hotels, gyms and more places.