Anc in-ear earphone Driver unit 2pcs dia8mm Frequency response 20-20khz Impedance 32 ohm Sensitivity 113db, 120db (at 1 khz) Noise reduction level ¿¬p11db at 300hz Plug dia 3.5mm Cord length 2.0m Battery aaa 1pcs We combine active noise cancellation with style. Comfort and sound quality to create a full, rich sound anywhere you use them. Thanks to the soft ear cushions and lightweight design you'll enjoy superior comfort for hours of listening pleasure. Plus, you'll experience optimal sound quality and speech clarity even at lower volumes, easily adjusted by the in-line volume control. Requires one aaa battery (not included) .It is compatible with all ipod, mp3, cd, dvd players, computers, in-flight and home entertainment systems