This worked within hours. I have a cat who is bored of shutdown as she loves people and none coming in to the house due to shielding. She goes out to anyone nearby and not a lot of those either. She has no off switch! Loves her brother but torments him and he retaliates then so does she. Three vet trips for chewed legs and infections and others I’ve treated at home in three months. Vets recommended the plug in and it worked. Then after 3 weeks, when no cats about, turned it off and forgot about it. One week later he’s tried to take her face off. Vet no. 4 for a gaping hole right through to her mouth. I’ve had to accept the smell as nearly £100 a visit was becoming a bit much! Arranging neighbours to take one or other in wasn’t ideal either. Been plugged back in for nearly two weeks and all is peaceful again.