I have the Petsfly wings carrier and I got the medium as I can fit all 3 yorkies in when I need to and 2 fit really nice. I can also fit my 10 lb wide bodied pom in it by herself. Here's a few pics from the other day. I put the carrier out to go get Pixie from her dental surgery and Cali and Roxie climbed in. I can fit all 3 in but it is tight. They are not very tall and are not flexible, but are very sturdy |