This is a CASIO PRT-40FSJ-3AT. It's an older Pro Trek model, but it's a valuable item as it comes with the original box and warranty. This model is not often seen on the market. The keyholder that came with the box is missing. The battery has been replaced with a new one, so you can use it as is for a while. It's from a non-smoking and non-pet environment, so there's no concern about odors or stains.