In perfect conditions. the Transmission range can be around 10 metres. (Some times more, some times less. All depends on the shape, size of the vehicle and the metal structure involved)
If the Sensor / Monitor is surrounded by large amounts of metal structure, the transmission range will be reduced.

To increase the transmission range, the TYREDOG™ TD-2000A Series contains a Relay / Repeater Module.
This module is required for Trucks, Buses, Motor Homes, Heavy Duty Vehicles and vehicles with a Trailer or Caravans.
The Relay / Repeater module must be mounted within 10 metres range of the Sensors but can be up to around 30 metres away from the monitor / receiver.