This is a dual camera dash cam that can record video to the front and rear cameras. It can also be used to add GPS data to videos, which is useful in insurance or liability claims. The basic $100 Rexing V1 has a GPS port, but you need to add $30 for the add-on module. The more expensive $130 Rexing v1p has both GPS and the rear camera, but doesn't include a micro SD card in the box.