Please refer to the second details picture on the left side and choose size mainly accordging to CHEST since it's a two-leg item. Very adorable.Your dog looks like a princess. Perfect for outdoor, take photos, Christmas and everyday wear . Take each measurement a bit loosely and if any of the measurements are 'between' two sizes, or your dog is still growing, larger size is recommended. Don't buy a particular size because that is what you always buy in a pet shop or online store, look at the size chart for CHEST and BODY and confirm the size before buy. Use the cold water and hand-wash, the items should be stored in dry and ventilated room environment and when it's not needed in a certain time .