Feature:1. BONE CONDUCTION TECHNOLOGY: Mini bone conduction pillow speaker uses the latest bone conduction technology to deliver sound to your ears through your pillow in a vibrating, compact and portable way.2. SOFT WHISPERING SOUND: pillow speaker is a soft whisper that helps relieve stress and helps you fall asleep faster. The mini size and low volume design is best suited for side sleepers.3. VERSION 5.3: Portable pillow speaker uses version 5.3 for stable and clear sound. Built in advanced rechargeable lithium battery that can work for more than 10h and recharge time is only 2h.4. TIMER FUNCTION: Bone conduction speaker has a timer function, double click the volume plus button to automatically timer off after 60min and double click the volume minus button to automatically timer off after 30 min.5. DEEP SLEEP: sleeping 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: Pillow SpeakerMaterial: ABSProduct Size: Approx. 15.5x3.6x1.2cm / 6.1x1.5x0.5in Version: V5.3Frequency Response Range: 100HZ-20KHZCharging Interface: Type CInput Voltage: DC 5V 400mAOutput Power: 3WSignal To Noise Ratio: ≥75dBWaterproof Rating: IPx 3Support Format: Small Memory CardPlayback Time: 20H (At 70% Volume)Battery Type: 400mAh Lithium Ion Battery (Built In).Package List:1 x Pillow Speaker1 x Type C Charging CableNote:Please allow some error due to manual measurement.