Dr.NONO is focus on bringing your pet health and happiness in their daily life. Take this Adorable pet dress enjoy your summer vacation! Tips:The breed or weight of your dog DO NOT determine the clothes’ size!Your pet usually wears size S doesn't mean all size S will fit him/her!!!So please measure your dog and have a reference before your purchase according to the size map(PS:According to our customers reviews,you can order the larger size)  Size: S (back length:9.8", Chest:13.7", Neck:9.8") M (back length:11.8", Chest:16.5", Neck:11") L (back length:12.5", Chest:18.8", Neck:12.5") XL (back length:13.7", Chest:21.6", Neck:13.7") 2XL (back length:14.9", Chest:23.6", Neck:14.9") If any of the measurements are 'between' two sizes, please choose the larger size. If your pet dog is growing up,you can order a bigger size.Take each measurement a bit loosely, so there will be room for your dog to move and breathe, but not too loose.  Please measure carefully before buying and contact l us if you have any questions about fit before you bid or make a purchase."