PNGKNYOCN 8.4V Battery Pack Housing, with DC and USB Ports Waterproof and Safe Battery Pack Housing, Suitable for 2/4 x 18650 Rechargeable Lithium-ion Battery Bicycle Lamp Headlights and Mobile Phones - YOUCHENG, 20211104001

• 4x 18650 battery rechargeable waterproof case with DC and USB ports. DC port is used to connect charging or 8.4V bicycle lights, USB port is suitable for connecting 4.2V bicycle lights or charging mobile phones (designed for bicycle headlights) 8.4V DC 5.5mm x 2.1mm input and output, 5V is USB output, USB output current: 2000mAh, the power switch only controls USB5V power supply It can be used with 2 or 4 18650 3.7v rechargeable lithium-ion batteries of any capacity power status indicator shows 3 green indicator lights to show the battery power status: three lights are on (power ≥80%). 2 lights are on(power ≥50%). 1 light is on and flashing (operating time ≤ 30 minutes, the battery needs to be replaced or recharged). It is most suitable for 8.4V, 1000mAh charger, the battery box indicator does not work when using the charger.Velcro makes installation more convenient and quick