MZ4 M-Series MZ-4 Wireless Speaker Features: Perfectly sized for portability making it the perfect speaker to take with you on your travels. 5W speaker with built-in PBE™ (Passive Bass Enhancer) that gives a rich and robust sound experience. Up to 26 hours continuous playback from one charge of the built-in 1200mAh rechargeable lithium battery. Pair with another MZ-4 speaker (using TWS mode) and play simultaneously. Specifications: Speaker5W Frequency100Hz-16KHz Play modesBluetooth® Battery1200mAh lithium, 3.7V Play timeUp to 26 hours Charge timeUp to 2.5 hours Bluetooth® versionv5.0 Operating distanceUp to 10m (33ft) Built-in microphoneYes Water resistantIPX4 TWSSupported Dimensions93mm x 95mm x 48mm