I have the front pet backpack that Cosmo can sit in or lay down. He LOVES it and I feel his safer than walking when we attend outside events like the local farmers market, craft fair, oh and camping! My daughter and I also ride bikes alot and he loves to be in the bag, plus I will put his heat disk or a small fleece blanket when needed. He is 5.9 lbs and I have the medium backpack. We originally bought the one with his leg out and he did not like it all, plus he looked really funny! The pet store let us return it