S. size harness & lead Set of 2 ① New, unused yellow ② Navy, tried on once The check pattern has large ribbons, making them very cute. The lining material is also mesh, which is gentle on the skin. * Navy chest circumference Inner button flat measurement: 18.5cm Outer button flat measurement: 17cm * Yellow chest circumference Inner button flat measurement: 19.5cm Outer button flat measurement: 18.5cm Both are labeled as size S, but I hope this is helpful. Please note that these measurements are approximate.