Instruct: Classify the given Amazon review as either positive or negative.
Query: Great Purchase

Recently got our first dog and did not know anything about training. After a month it was apparent the dog was not going to stay in our yard so I purchased the PetSafe Dog Training Collar. Long story short, in 1 day my dog was trained and knew exactly where he was and was not allowed to go. I was amazed and now only use the sound option to provide minor corrections. I would highly recommend this to anyone who has problems training your dog.