KZ ZS1 IEM Sports Headphones with Dual Drivers, Extra Bass and Wide Sound Field, Standard Edition Cavity mold using a high purityresin made transparent pan-black,more of a mystery. Independent sound channel for each driver, the sound will not be distorted. Gold-plated jack, HiFi lossless cable, sound connection to your audio device. Dual driver speakers, complement each other; bass, mids and treble is rich and energetic. Ergonomic ear radian own patented design,can greatly enhance the sound conductior properties.