I bought this about four years ago! I replaced all the filters last summer. I've used it a bit since then, so the back of the green filter has changed color slightly. I'm selling it because I don't need it anymore due to moving. I'll be getting rid of it at the end of November, so please consider purchasing it before then! There are no problems with the operation, so I think you can use it without any issues. I've thrown away the original box, so it's not included. I have the instruction manual, and I will include it. This is a used item, so please only purchase it if you understand that.