Specification Dimensions : 34mm x 28.5mm Net Weight : 33g speaker Parameter : 4Ω 3W Frequency Response : 20Hz - 20KHz Battery Capacity : 200mAh Battery Charging Voltage : 5V Playback Time : 40 - 50 minutes (in MAX volume) Battery Charging Time : 1 - 1.5 Hours Compliant : Bluetooth V5.0 Items included: Mini speaker 3W with Bluetooth Function x 1 Micro-USB cable x 1 Dual Pairing Function - It is available to use 1 mobile phone to control 2 mini speakers at the same time. Manual Steps : 1 ) Long press the ON/OFF button of 2 mini speakers, then 2 mini speakers are in standby status. 2 ) take 1 standby speaker as main one, double quick click ON/OFF button, you will hear a voice , then 2 speakers are connecting. 3 ) Open the bluetooth of your mobile phone and connect the "MT" as usual , then you can control 2 speakers at the same time.