I used it a few times right after I bought it, but I haven't used it much since then and have been storing it. There are no instructions, only the main unit and the tray. I have cleaned it as much as possible with alcohol. Also, I tested it with water, and there were no problems with water absorption, etc. I have placed a yellow sticker on the water tank to indicate the full water level. It will be shipped wrapped in bubble wrap and placed in a reused cardboard box. Returns are not accepted, so please purchase only if you understand this.