Metal carabiner is designed to protect the speakers from damage and allow you to easily attach the speakers to your backpack or belt loop Bluetooth 4.2 ensures instant pairing and stable connection, with clear sound quality and loud volume With improved durable fabrics and a sturdy rubber case, protecting your speaker in all your adventures The LED indicator will remind you when the speaker is out of power, charging, pairing mode, or receiving calls. It also notifies you when the speaker is not connected via Bluetooth or is answering a call Lightweight but robust body design provides the perfect sound for you