This is a harness for medium to large dogs. Size M (see photo 2) I planned to use it for a Golden Retriever, but I didn't end up using it. Dog Walking Assistance Harness For senior dogs, care supplies, for weak legs and lower back, for rehabilitation after surgery, medium-sized dogs, leash, body harness, for pets, for hind legs, for disabled dogs, for mountain climbing Walking assistance, care for senior dogs: Can be used for the care of senior dogs with reduced physical strength or weak legs, lifting them into cars or up stairs, at the entrance, and for walking with a support seatbelt. Can be used on the pet's waist, legs, and chest. It also supports the recovery of dogs with injuries or arthritis. Soft material: Dog bag, soft, durable, light and flexible, with a mesh lining, excellent breathability, and quick-drying. The fluffy habitat of the dog seatbelt helps prevent friction and pain, providing ultimate care for disabled dogs. Adjustable: The long and thick lifting belt and soft non-slip handle are sturdy walker belts that won't burden your pet.