Size M, neck circumference 14~17cm, chest circumference 18~24cm, back length 10cm, suitable for ferrets, etc. Comfortable: Made of hard-wearing mesh material and nylon, Breathable and padding, Soft harness with fully elastic leash of 47 inch,which lets your bunny have lots of freedom Please measure your pet size accurately before placing an order! If your pet’s chest girth is between the two sizes, it is recommended that you can choose the larger size and adjust the strap to prevent the harness from being too small Various Advantages: The harness is quick and easy to put on due to , it can be washed at 30 degrees and colorfast Adjustable: Extra nylon strap with snap buckle, you can adjust the harness at chest and stomach, more fit to your pet,better and easy control, which keeps him from slipping out