This is the second such backpack! I'm delighted. The first ordered M from another seller. But M for one dog (I have two Chihuahua: 2,1 kg and 3.6 kg). The second backpack ordered from this seller, size L. to Moscow delivery month. My two Chihuahua fit perfectly. I apply photos for comparison. I recommend, if the dog is small, take m. If the dog from 3,5 kg-then definitely m will be too small (the dog will not lie down, only sit can), it is better to take L. Size M. For 1 dog up to 3,5-3,6 kg the maximum will be perfect. But in fact 2.1 kg is straight in general super, it lies comfortably and sleeps there, not at all cramped. But the dog 3.6 kg-it is cramped to lie, but if you go not long, an hour or two, it will be normal.
Everything corresponds to the description, before St. Petersburg it was almost a month, carrying cool, the dog fit
Just delighted with this backpack! My Chihuahua in it is spacious, nowhere rests, a review from all sides. Sewing at the backpack on conscience, hard bottom and back, which is very convenient for both the dog and the owner. Many thanks to the seller for such a wonderful, comfortable and functional thing!