A quick bit of online sleuthing revealed that ID is attached to a microwave sensor module. Most of us would probably expect to see a PIR sensor, but this light is motion sensing with microwaves.

It has unique microwave motion sensor module with micro-strip patch antenna. It also has advanced ASIC-based electronics height installation calibration free 2-way PIR/ microwave sensitivity ...

It has unique microwave motion sensor module with micro-strip patch antenna. It also has advanced ASIC-based electronics height installation calibration free 2-way PIR/ microwave sensitivity ...