BlackVue DR970X-1CH Plus Quick Start Manual page 12

Peel off the protective film from the double-sided tape and attach the front
camera to the windshield behind the rear-view mirror.
Adjust the angle of the lens by rotating the body of the front camera. We
recommend pointing the lens slightly downwards (≈10° below horizontal), so as
to record video with a 6:4 road to background ratio.
Peel off the protective film from the double-sided tape and attach the rear camera
to the rear windshield. Adjust the angle of the lens by rotating the body of the
rear camera.
Connect the front camera ('Rear' port) and the rear camera ('V out') using the rear
camera connection cable.
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