Dual balanced armatures sound engine for high dimensional sound stage. Armature sound drivers are usually better performers, and more expensive to produce, than dynamic drivers. Acoustic Horn New horn shape design enables a highly accurate playback. The pipe shape allows sound to propagate in a direct radial motion to your ear. Type Dual Balanced Armature Frequency Response 20~15,000 Hz Sensitivity 111dB/mW Impedance 37ohm Output 3mW Cord Length, Shape 1.2m, Y Weight 4g Weight in Retail box 70g Standard Earbud ER-CK9, ER-CK100		Contents .. Audio-Technica ath-CK90PRO 3 pairs Silicone ER-CK9 earbuds (S, M, L) 1 pair Foam ER-CK100 earbuds Pouch Supplied by Authorized Resellers in Japan. Japan Warranty 1 year on labor & parts from the day we sent your parcel. We can help you liaise with the Japan repair centre. You will pay for postages to/from our Japan office, and within Japan.