Connection method: BT connection Frequency response range: 100HZ-20KHZ Signal to noise ratio: ≥ 85dB Number of speakers: 1 Effective distance: 10M Box material: plastic Appearance size: 97 * 97 * 80 Article number: Q21 Power mode: USB Waterproof grade: non waterproof BT version: 5.1 Rated power: 6 Net weight of product: ≈ 0.42 Rated voltage: 5 Additional features: card insertion Built in battery: Built in battery.