Mifa Bluetooth Speaker - F4 (Grey) Storage type: Max. 32GB micro SD card, Power supply: Built-in 800mA lithium battery DC 5V-500mA USB adapter Loudspeaker: One 40mm speaker, RMS: 3W 4ohm Frequency Response: 110Hz / 15KHz, Bluetooth version: Bluetooth: 2.1+EDR USB specification: USB2.0 compatible with USB1.1 1 Year Limited Warranty