I have had Teentok/Techalogic cameras for a couple years now and they work well. They last about 5 hours if the light is of, and get clear enough shots to read the license plate of almost any vehicle that comes closer to me than it should. Since it has a GoPro style mount you can buy mounts to suit your needs, but the one that comes with the Techalogic works well on my seatpost. I got a steer tube spacer one for the front camera. FWIW I find a front camera to be quite useful for when the jerk with no front plate passes me.
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