Power kit can prevent car battery disacharging by blocking power to the dash cam or car blackbox if the voltage drops below a configured value or if the configured time has elapsed.

Direct wire your FineVu CR-500HD dash camera to the fuse box Power Kit should be hardwired to a constant-on 12V power source, so the dash camera will remain powered when engine is off.

Blackvue DR400G HD Mount Holder

Lukas Circular Polarizing Filter reduces oblique reflections from non metallic surfaces to get better video image with car dash camera.
It also reduces glare from direct sunlight into camera lense.

With T Power C , your dash cam stays awake 24 hours with uninterrupted power supply. 
T power C doesn't discharge your battery while keeping your dash cam alive for upto 24 hours.