Bluetooth Bicycle Speaker w/ Microphone and Mount. For Nokia Lumia 920, Nokia Lumia 820, Nokia 808 PureView, Nokia Lumia 900, Nokia Lumia 810, Nokia Lumia 822, Nokia Lumia 521 / 520 &More Digital Devices Play Music & Make Calls Via Bluetooth Splash Proof, Durable Bluetooth Speaker | Tightly Attaches to Bicycle Frame Adjustable Volume | Play/Pause Buttons | Comes with a Built-In Rechargeable Lithium Ion Battery; via Micro-USB Cable (Included) 3 Hours of Working Time | About 25-30 Hours of Standby Time Frequency Range: 80Hz ~ 20KHz | Sound Output 2.0 Amplifier Output