The Dog Helios ® Freestyle 3-in-1 Explorer Sporty Convertible Waterproof Dog Backpack Harness is a Backpack that Doubles as a Chest Harness with an Included dog Leash. This Only-of-its-kind 3-in-1 Backpack, Harness and Leash features a Backpack with a Chest Compressible Harness that completely ejects from the Backpack that enables the user to remove the backpack as the user wishes. The Dog Backpack Harness features a special DUPONT Outer-shell that is entirely Waterproof including the zippers. The Outer shell of the Backpack further features reflective-tubed lining all around with added reflective memorized stitching along the DUPONT Nylon material for premium protection during those night strolls. These dog backpack harnesses features both a Neoprene and Waterproof DUPONT exterior with a breathable and visible cross-stitched inner mesh Outer and Inner lining for optimum comfort. The Chest Compression Harness is also fully adjustable and places little-to-no stress at the sternum area of the pets body for a comfortable pull. Comes with a matching accented Nylon leash with a Stainless steel swivel hook. Features Rubberized Stitching and Embroidery at the Leash, Backpack and Harness. Get Outdoors with Helios Dog! This Backpack Harness for Dogs is Available in Multiple Sizes and Colors. SIZING GUIDE (INCHES) - BACKPACK/HARNESS - SMALL - BACK - 7.48, CHEST - 17.7 - 22.8, NECK - 15.7 - 18.8 MEDIUM - BACK - 8.26, CHEST - 21.6 - 27.5, NECK - 19.7 - 24.4 LARGE - BACK - 9.1, CHEST - 24.4 - 33.8, NECK - 26.7 - 34.4 LEASH DIMENSIONS - SMALL - LENGTH 4 FEET, THICKNESS - 0.27 In MEDIUM - LENGTH 4 FEET, THICKNESS - 0.35 In LARGE - LENGTH 4 FEET, THICKNESS - 0.51 In