In-Ground Fence Prf Large Breeds (PRF3004XW-20)

Invisible Fence Pet Safe Prf for Large Breeds
For dogs weighing more than 18 kg.
Up to 1,500 meters of perimeter.
Receiver with 5 intensity levels. Level 1 includes tone and vibration.
Collar: operates with a standard 9V battery. Submersible
Transmitter powered by 220V. The range can be adjusted from 50 cm to 150 cm.
Cable (150 m) and flags (50) included.

This is how invisible fences work.
The area assigned to the dog is defined by a cable connected to a transmitter. The cable can be installed in any configuration; it can even be buried so that it cannot be seen or obstructed.
The dog wears a training collar. When the dog approaches the area where the cable is located, the collar emits a beep to prevent the dog from continuing to approach. If the dog persists, the collar is activated and delivers a small deterrent pulse that makes the dog retreat.
The dog quickly learns to respect the boundaries of its territory.
You can create cable-free zones so that the dog can move freely across the cable. During the first few days, flags help you identify the boundaries. They can then be removed.