How does TireGuard TPMS work?

This is a high quality new generation system: self-programmable and easy to transfer to another vehicle.

Each tyre gets fitted with a tiny Internal or External sender unit that simply screws onto the valve stem in place of the valve cap.
The External sensor simply screws onto the valve stem in place of the valve cap. The Internal Sensor replaces the valve and is installed at a Tyre Shop.
This sends a radio signal to a monitor that looks like a small cell-phone, which checks the readings against parameters that you have set for that specific tyre, warning you when it is at risk.
You may at any time check each tyre's pressure and temperature by repeatedly pressing a single button.
You can reprogram limits for any wheel in seconds. This is a new generation system which overcomes deficiencies of previous systems.
Niceties abound, from user-replaceable sender unit batteries (CR1632 which lasts a year) to monitor battery recharged from a lighter socket every two months or so, giving the system an indefinite life.
Transferable to another vehicle in a minute. (Take it on holiday and fit to the hire car, one never knows how their tyres have been abused.)
Comes standard with six sensors, so the trailer with your precious toys on it, is covered. Expandable to 22 wheels.