What are the vehicles that it can jump start?
For jump starters, we guide you the range of products for which they may be used based on the displacement volume. A J20C product allows you to jump start an up to 6,000cc gasoline and LPG or 3,000c diesel 12V vehicles. Prior to making a decision for purchase, please check the displacement volume specification of your vehicle (vehicle registration certificate).
It says 12.8V 4,000mAh on the back of the product but isn’t the capacity 16,000mAh?
A J20C product has four 3.2V 4,000mAh battery cells connected in series.
This is the correct battery capacity written in accordance to the Product Specification Display Act so please do not misunderstand.
I would like to use it in while I am outdoors. How long can I use it for?
A J20C product is capable of 5V output on USB and 12V output through the cigarette lighter socket. When using 12V, you may use up to 10A electronic devices (120Wh) and the range that guarantees stable use is within about 100Wh. Also, the battery capacity is about 12V 51.2Wh so, if you use a compatible 10Wh electronic device, it is safe to think that you may be able to use it for about 5 hours. Please check the power consumption specifications of the electronic device you wish to use.
The product doesn’t work even if it’s been charged for a long time.
Please check if it’s the correct charger for your product and completely separate the charging adapter from the product before trying to reconnect. If it has been stored and left alone for a long period of time, a difference in the current and voltage may have been created, which can be a reason for the charging time to take twice as long as average. If the charging time is unreasonably long or a device malfunction is suspected, please contact our customer support center. Because this product is an electronic device with an embedded battery, if it is left alone for a long time, it will be completely discharged and can no longer be used even after charging. If this is the case you will also incur after-sales service costs for battery replacement, etc. so we recommend that you charge it once every 2 to 3 months.
When jump starting a car, an alarm rings even when I just connect a smart cable with the product.
If an alarm rings when the product and a smart cable are connected with each other, even when it is not connected to a car battery, it is a low-voltage alarm that rings because the product has a low voltage. It rings as the voltage falls below the state in which the car cannot be started and, in such a case, you can connect it to a home adapter (charger) and completely charge the product before using it again. The remainder display lamp of the product does not show the voltage so, if an alarm rings even when you just connect a smart cable to the main body, please charge it before use.
The car wouldn’t start even after connecting the battery and pressing the booster.
If the green lamp is turned on after connecting the battery, the boost feature will not be activated even if you press the boost button. In such cases, please check via the following method.

1. Connect the (+) terminal and the red clamp of the car battery
2. Press the boost button for about 2 seconds (check for a clicking sound and the green lamp to be lit)
3. Connect the (-) terminal and the black clamp of the car battery
4. Start the car
Can I use it overseas and get on a flight with it?
All electronic devices with embedded batteries must be brought into a flight with carry-on luggage, rather than being sent in checked luggage and, because the allowable battery capacity may vary for different airlines, be sure to contact the airline before bringing it onto the aircraft. The rating of the exclusive charger is between 100V and 240V so, if it is within the correct range of usage, you may be able to use it with a transformer (universal adapter).
What are the components of the battery?
It is embedded with a battery made of lithium ferric phosphate.
If it continues to be connected to the car battery, will the car battery be charged as well?
Even if the product is connected to a car battery, it wouldn’t charge the battery.
Our product is for emergency jump starts in case of vehicle battery discharge so it can only be used for such purposes and, thus, after a jump start of a car, it needs to be separated from the car battery immediately. If it continues to be connected to the car battery before and after a jump start, it can cause device malfunction.
Can it be used on buses and large trucks as well?
A J20C product is a 12V exclusive product so, for such usage, please check out our JX-02 product, which can be used for both 12V and 24V batteries.

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