Our newest harness Ares, (Denise Panis and Ares helped us finish the size) it is a midsize between the Medium and the Dixie. It fits 2 distinctly different body types (sometimes things are just funny). It fits wider body dogs with a long round rib cage or the larger narrow body BC with a shorter shoulder (all legs). It works where the Lucy Medium front chest will sit too high in the throat and the Dixie will sit too low or below the breastbone. The soft reflective chest strap, flexible saddle, and ultra soft webbed girth keep the dog's range of motion flexible while the reflective outline keeps them visible. Thus, making it great for nose work, disc dog, flyball or any other canine sport that you and your pup may be involved in. Have fun with the coolest harness in or out of town.