These powerbanks are specially designed for use in dashcams. The power bank or battery pack is an external battery that you can use to supply your dashcam with power. You connect the power bank directly or with a car charger to your car battery and the dashcam to the power bank. So you actually place the powerbank between the car's power supply and the dashcam.
While driving, the powerbank is simultaneously charged and the dashcam powered. When the car's ignition is turned off, the power bank's capacity is used to power the dashcam. This way, you can also use the dashcam as security while parking without fear of running out of battery power.
