Product description    Small lightweight body that fits snuggly into the ear with ■ a new design drivers enjoy the high-quality sound and clear. The diameter of the inner-ear headphones is usually about 17 ~ 18mm， but I realize smaller size and about 15.8mm in this product. ■ (depends on the version of software or iPod / iPhone / iPad) easy operation at hand and adjust volume / back play / pause / track forward / track design ■ music and video image of a glass pour sound ■ condenser microphone place the remote control in correspondence ■ code bifurcation such as Siri and a call on your iPhone and a built-in