Our bark training collar combines 2 vibration modes with 7 sound stages. Once you have chosen the desired mode, the vibration and sound level will automatically increase in intensity whenever your dog barks for more than 1 minute. Once your dog stops barking for 1 minute, the collar will automatically reset to step 1, thus providing immediate training feedback to your pup! 5 sensitivity levels It’s quick and easy to set the vibration collar to the right sensitivity level for any occasion! Level 1 is the least sensitive and it’s ideal for when you’re out and about surrounded by lots of noise or watching TV. Level 5 is the most sensitive; perfect for low environmental noise, like at night time or when you’re alone with your dog.