Ideal for schools, libraries and training departments, the ED1TCi communication headphones incorporates a plastic ear cup that allows easy cleaning with maximum durability for a multiple user environment. The in-line microphone allows for easy communication and works well in an education or commercial setting. An adjustable headband allows for custom comfort for all ages. The ultra-durable design, adjustable headband and in-line microphone create the ideal headphone for any commercial or institutional environment. Simple to use, push-to-talk, and in-line microphone allows users to quickly and easily take a phone call while listening to their favorite music. Compatible with most mobile phones that provide a 3. 5 mm audio output jack, the addition of the in-line microphone gives these headphones an exciting new option. Durable Commercial & Institutional Headphones. Plastic Earcups For Convenient Cleaning. In-line Push-to-talk Microphone. Durable Design For Multiple Users. 4ft With A 3. 5mm Plug. Covered Under The Koss Stereophones Limited Lifetime Warranty