S:14cm x 13cm x 6cm -- recommended dog weight up to 10kgs;L:17cm x 16cm x 7cm -- recommended dog weight up to 15kgs. Made from high quality pu leather , durable for long time. easy to put on and take off.Not only a small backpack, but also a cute dog costume. Can fit medium to large size dog such as Alaskan, Samoyed, Shepherd, Tibetan mastiff, etc. Please check the size. Adjustable straps fit for your better use. Large Capacity - carry food, water bottles, poop bags, toys, first aid, or other daily supplies become more easily. Adjustable straps to provides a easily fits for different kinds of Medium & Large dog, such as Border Collie, Cane Corso, Great Dane, Pit Bull etc.