This is the patented harness that prevents puppies or small adult dogs from escaping fenced-in areas. The device slips on a dog like a common harness, but its integrated rigid 10 1/2"-long cross-bar spans well beyond the width of the pet, preventing it from slipping out between fence railings. The lightweight harness won't inhibit a dog's movements and allows passage through most standard pet doors. It is made from a 100% woven nylon that pets won't find irritating, and has adjustable straps to ensure a snug fit. Specify small (10"-16" chest) or medium (12"-20" chest). Red. 11" L x 4 1/2" W x 1 1/4" D. (2 oz.)