【BT:Bluetooth】BTmeans Bluetooth.You can use your phone or I pad to play background music for your workout. 【Two speakers】6.5-inch woofer shows the bass better, 2-inch tweeter shows the treble well. 【Multipurpose amplifier】It can be connected to your electronic drum, keyboard or another instrument 【Portable design】Small size and light weight. It can running to a family practice, lesson or any situation. 【USB interface】USB interface, which can insert U disk to play music
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