Audio-Technica's ATH-CK9 QuietPoint passive noise-reducing earphones deliver outstanding isolation from distracting background noise. These in-ear models are equipped with an ultra high-quality balanced armature driver that offers crisply detailed high-fidelity audio, reproducing the subtlest of sounds. Without the use of active noise-cancelling electronics, ATH-CK9 QuietPoint earphones achieve significant attenuation of outside sound, allowing for increased fidelity and acoustic impact at lower volume levels. Ideal for use with all audio sources, including MP3 and other portable players, they are supplied with interchangeable ear pieces for a comfortable, custom fit.