* Perfect ear， wear more comfortable* The built-in support for hands-free calls and Internet chat microphone* Ultra flexible， flat wire without knotting Speaker size :13.5mmSensitivity:100±3dBFrequency response range from 20 hz to 20000 hzImpedance:32 ΩEquipped with a diameter of 3.5 mm plugLine length is 1.3m cables