This is by far the best convertible booster seat you can buy. It can start as a high back booster and can change into just the seat/backless booster. It has very little wear except for a few marks on the base seat cover which I will try to get out. It is made with a metal frame and washable cover. This seat was purchased in April 2011 and has no expiration date but WA State recommends replacing seats every ten years thus until April 2021. It has never been in a car accident. It comes with the owners manual but you can get more info on their website if u go to Google and type in Clek.