Alfie Pet Apparel by Petoga Couture - Koji Diaper Dog Sanitary Pantie - (for Girl Dogs) Best fit waist girth: 12" - 16". Sizing for each dog is unique. Similar to our clothing and accessory, medium size from one designer is not the same for another. For example our 9-pound yorkie model usually fits either one of three sizes (i.e. XS, S, M) depending on the designer. We highly recommend you measure your pet precisely with a flexible tape measure to ensure the best fit. Contact us if you have question. We are happy to help. Eliminates problems from untrained pups and females in season, incontinent dogs and excitable urination. Place adhesive napkin on inside of garment to adsorb liquids. Washable and reusable. Made of nice soft cotton, very comfortable for daily wear. Alfie is a registered trademark and is exclusively distributed by Petoga Couture. Alfie trademark is protected by US Trademark Law. Use is strictly prohibited. Other seller offerings are counterfeits, they will not be identical to what is advertised here. Petoga Couture ship from US thru Amazon therefore all orders with them are eligible for FREE Super Saver Shipping and Prime Shipping Upgrade.