Audio Technica ATH-ANC23 QuietPoint Active Noise-Cancelling In-Ear Headphones - Manufacturer Refurbished Ultra-compact in-ear design is ideal for travel Advanced electronics cancel up to 90% of background noise Innovative ANC circuitry delivers an exceptionally pure audio signal in noise-cancelling mode Ideal for use with all audio sources, including MP3 & other portable players Soft interchangeable ear-pieces (small, medium & large) provide a custom fit