While the vast majority of dash cam systems we install these days are 2-channel (front and rear) setups, some drivers are interested in equipping their vehicle with even more coverage and protection. With this Fiat 500L, we installed two sets of Thinkware F800 Pro with two separate Blackvue B-124 batteries. The two main front cameras are installed with one on the front window and one on the rear window. The "rear" cameras are mounted on the C-pillar facing out the rear door windows. From this angle, the camera can catch things like door dings, vandalism, and help in the event of a sideswipe.
We installed two separate B-124 batteries instead of using one B-124 with a B-124 expansion battery. Although the total battery capacity would be the same, two separate batteries charge to 100% in just 40 minutes whereas a B-124 + expansion would take double the amount of time to charge. It's rare that we come across drivers that drive an hour and a half in one go so the quicker charge time makes sense although the wiring is a bit more complicated, we think it's worth it and don't charge our customers any extra. In this car, there's plenty of room under the seat to mount extra batteries and expansion batteries can be added should our customer choose to do so down the road.