Reflective Mesh Soft Vest Dog Puppy Pet Harness Adjustable Medium Size: Neck 14" Girth 13.5"-14".The velcro strap will adjust about 1 to 2 inches. Light-weight Soft Breathable air-mesh 100% Polyester Material. The harnesses provide owners with a secure, comfortable, and controlled way to walk their pets. Gray Night Safety For Safer Night Walking. IMPORTANT:Please do not purchase the harness based on the size of another manufacturer/designer.You have to take various measurements into consideration before you purchase this harness.