These Sony MDR-NC33 in-ear headphones cut out up to 90% of ambient noise while travelling or listening in busy environments. Up to 100 hours uninterrupted listening time from a single AAA battery. Featuring a powerful Neodymium driver unit for rich smooth sound and powerful extended bass. The MDR-NC33 headphones are designed for excellent listening comfort and have a vertical in-ear design with 3 sizes of silicon ear bud for a great fit and minimal sound leakage. The headphones come with a protective carry pouch and in-flight plug, perfect for frequent travellers always on the move. Convenient built-in clip easily attaches to clothing.