Product Features:1. Custom upgrade line of KZ bluetooth module.2. Advanced Wireless Bluetooth 4.2 Upgrade Module.3. The KZ headphones in your hands, extraordinary, and the cable connection can give you a professional listeningIncisively and keenly, and wireless connections can let you in motion is put aside all, enjoy the experience.4. Live freedom from now on.Color Classification: Type A (for ZS3/ZS4/ZS5/ZS6)  Type B (for ZST/ES3/ZSR/ED12)