I have the Graco Nautilus. It converts from a 5 point harness to a high back booster to just a booster. I loved that I could put dd in it after outgrowing her Marathon booster and still keep her in a 5 point harness even though legally she could be in a booster. Legally doesn't mean she would sit right in it though. I got to put her in a 5 point harness until I thought she was ready for the high back booster. Plus, I could easily put her back in the 5 point harness if I was having issues w/ her listening on the proper way to sit in it.