This product delivers an electric shock in response to a dog barking more than three times in a row. By repeating this process, the dog learns that barking results in a shock. Important Notes: This product is a dog training collar that uses electric shocks powered by batteries. Please adhere to the following guidelines: 1. Do not use for purposes other than dog training. 2. Do not use on dogs with heart conditions, puppies under 6 months old, pregnant dogs, obese dogs, or elderly dogs. 3. Do not use on extremely timid or easily excitable dogs. 4. Do not use for more than 8 hours a day. 5. Store out of reach of children and pets. 6. Use only the specified battery type (9V manganese battery). Since this is an unopened product, functionality has not been verified. Please refrain from requesting a warranty.