Portable bluetooth speaker

Type: Bluetooth speaker
Connection method: Bluetooth connection
Interface type: USB
Battery capacity: 4000mah
Frequency response range: 50HZ-20KHZ
Output power: 30W
Signal to noise ratio: ≥75dB
Power supply mode: built-in lithium battery
Channel: 2
Play time: 8 hours
Expansion storage: 32GB
Bluetooth protocol: 4.2
Number of speakers: 2
Effective distance: 30 meters
Function: card, remote control, waterproof, dustproof, anti-drop, call function