I am so happy with these two products. The Sidekick leash and supporting book are amazing tools. I am an instructor at a dog training facility and despite my years of experience have struggled with my young male aussie and his reactivity. This leash is the only piece of equipment or training that made the difference. It created a connection between the two of us that nothing else came close to. I will be recommending your product to my students in the future and teaching w/ mine in the classroom