Dogline Alpha Multipurpose Pet Dog Nylon Harness with Removable Chest plate and Therapy Dog Velcro Patches. These harnesses are perfect for Therapy dogs, therapy dogs, medical alert dogs, law enforcement and a lot more. These harnesses can be used for walking, biking, hiking, tracking, hunting; various support tasks and a lot more. These harnesses are made of durable breathable nylon with neoprene lining. Machine washable and weather resistant materials make this harness low maintenance and very practical in all life situations. These harnesses come with removable chest plate to provide maximum comfort for the dog. Chest plates and trim around the harness are reflective for maximum safety. EZ Grab handle provides total control of the dog in any situation. These harnesses come in 2 different colors and 4 sizes. Please measure your dog's girth behind front legs at the widest point before ordering. Small 18"-25", Medium 22"-30", Large 28"-38", X Large 36"-46". Small and Medium harnesses come with 1.5" wide nylon reflective chest plate and strap. S and M harnesses fit patches 1.5" x 4". Large and X Large harnesses come equipped with 2" nylon reflective chest plate and strap. L and XL fit patches 2" x 6".