Product Features 245g over-head headphones with 40mm neodymium driver, 8-25, 000 Hz sound range & 3m cord Crisp, dynamic audio with 40mm neodymium driver Open-air design delivers purer, natural sound Enjoy long-lasting comfort with a flexible ear fit 40 mm driver units for powerful, expressive sound Open-air headphones for experience natural sound field 300 k J/m 3 neodymium magnets for clear mid-range & rich bass sound Technical Details open dynamc 40mm driver unit 104d B/m W sensitivity 8-25, 000 Hz range 3m Cord gold plated unimatch plug adaptor