This strong sounding 3 watt line-in (3.5mm) speaker is also a 2200 mAh power bank. Great for smart phones and digital music players.Input: 5 V. Output: 3 W. Battery: rechargeable Lithium. Capacity: 2200 mAh. Plug: 3.5mm audio cable. Packaging: individual white box.2-in-1 Power Bank & Speaker. Strong sounding speaker and power bank. This strong sounding 3 watt line-in (3.35mm) speaker is also a 2200 mAh power bank. Great for smart phones and digital music players.