The Dog Line is very easy to use and the service is excellent. I purchased barking collars for both my dogs and the collars have worked on both. One is a Cavalier who is a nuisance barker but since using the barking collar she is happy to lay at the front door and just looks outside wagging her tail instead of yapping. My other dog is a Staffy who quite aggressively barks at the dogs next door, and he has also stopped barking (only when the collar is on - but it is a great starting point). I actually got a phone call from the company to see if they could help me in any way. Speedy delivery and friendly to deal with. Thankyou so much. Diane