I have a Siberian Husky and was looking for a way for him to get more excercise. I ended up getting a springer bike attachment, and it is wonderful!!! I was concerned that he would be able to pull me over but the spring on it so strong that even when he does pull to the side I am secure on my bike. I found this on the web, didn't find it in any store. So if anyone is looking for a way to exercise their dog(s) more, try this!!! I got it at www.allterraindog.com