With indoor positioning.
SRT306i is everything SRT306 is and more. It works exactly the same as an SRT306 when it comes to alarm functions, GSM/GPRS communication and GPS/GLONASS positioning. But SRT306i can also position itself indoors and in other environments where GPS/GLONASS is insufficient. In an environment equipped with SRT334’s.
SRT306i can receive position information through radio communication.