Mia has outward hound xs. she is 6 pounds and it fits fine. Last year when she was smaller, 4 pounds it made her a little lopsided in the water.
This year it is perfect. She swims in our pool lots. I usually only use it if she is in the pool for a very long time. I don't want her getting overly tired. Our pool is 75 feet long, so it is a big swim for her.
hope this helps |