The PestBye rat and mouse repeller uses both ultrasonic and electromagnetic waves to repel rodents from your home. Safe to use if you have cats and dogs, but not suitable if you have guinea pigs, mice, gerbils or hamsters.
The ultrasonic waves don't pass easily through walls and this is where the electromagnetic waves come into play. The repeller sends electromagnetic interference into the electrical wiring of your house, repelling critters up to 1 metre away from your wires. This is great as rats and mice will often use gaps in walls and between flooring, which is also where your wiring will pass.