Or a pen in the back seat impale itself 3" into the dashboard from a head-on. I always cringe when I read about people using portable power stations containing an AGM or FLA battery. How do you secure something of that mass while making it convenient to remove frequently? Cast iron skillet? Greenie propane bottle?If more people understood kinetic energy, they wouldn't be mounting things where they do. 30 mph into a wall, a two pound extinguisher sailing from the rear to the front will take your head off as it goes through the windshield. Tool boxs are a personal favorite and you should see what that plastic drink bottle (empty or not) does when it rolls under your brake pedal.