It does not block radar or autopilot sensors. TACC, parking distance sensing, etc. all work fine. The bracket slides into the upper part of the front grille (directly below the nosecone, above the radar) and the bottom of the license plate is attached to it. End result is that the plate sits in front of the nosecone, in the same position that it would be if you had it mounted by Tesla, except no holes are drilled in the car and you can remove it later without a trace.
The one issue I've noticed with The Law is that it holds the plate very close to the nosecone, such that if the plate is pressed in slightly, it will come into contact with the plastic. That was easily fixed: I just took a felt dot (1" diameter, the kind you put on the bottom of a chair leg so it doesn't scuff your floor) and stuck it on the back of the license plate.
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Sorry, your info is out of date. They sell an updated version for autopilot models.