I have two boston terrier puppies! My bostons are 14 weeks old and have just realized they can run off quickly! This leash is fabulous! I can walk or jog with my dog attached to me and he has room to move around. The elastic give of this leash keeps your dog from jarring you and tugging at your waist. I like that you have several clips to attach the leash to giving you the freedom to walk your dog on the right or left side. We live on a farm so this leash quickly got a bit dusty but it was a breeze to rinse off in the sink with some dawn dish soap.