Feature:1. BONE CONDUCTION TECHNOLOGY: Pillow speaker uses bone conduction technology to transmit sound to your ears by way of vibration through the pillow. Bluetooth version 5.3 ensures stable and clear sound.2. LOW VOLUME DESIGN: Wireless stereo pillow speaker is a soft whispering sound that helps relieve stress and helps fall asleep faster. The mini size and low volume design is best suited for side sleepers.3. TIMER FUNCTION: With a timer function, double click the volume up button for automatic timer shut off after 60 minutes, and double click the volume down button for automatic timer shut off after 30 minutes.4. RECHARGEABLE LITHIUM BATTERY: Bone conduction bluetooth music box has a built in premium rechargeable lithium battery that works for over 10 hours and charges in just 2 hours.5. PROFESSIONAL DESIGN: Bone conduction pillow speaker is designed to relieve stress and help deep sleep. Provides great help for adults and babies to fall asleep and get rid of the trouble of insomnia.Specification:Item Type: Bone Conduction Pillow SpeakerMaterial: ABSSize: Approx. 15.5x3.6x1.2cm / 6.1x1.4x0.5inBluetooth Version: V5.3Charging Interface: Type CInput Voltage: DC 5VOutput Power: 3WSignal To Noise Ratio: 75dBWaterproof Rating: IPX3Support Format: Small Memory CardPlayback Time: 20H (At 70% Volume)Battery Type: 400mAh Lithium Ion Battery (Built In).Package List:1 xBone Conduction Pillow Speaker1 x Type C Charging CableNote:Please allow some error due to manual measurement.