Dual zone microwave sensor, car alarm

[afm]

Hello, I would like to know how this sensor kit works.
I have an alarm with this type of sensor, but it is not dual zone, I would like to know how it works with dual zone, with adjustment "inside the vehicle and outside" and if it is better than mine.

I know how the sensor works in my alarm! I don't know how this works.

How does the sensor work inside the vehicle?
How does the sensor work outside the vehicle?

https://www.ebay.com/itm/New-DUAL-ZONE-PROXIMITY-SENSOR-for-any-bike-car-alarm/400350832159?hash=item5d36c4e61f:g:SX0AAOSwEetV-WYk

Thank you.