The CS505 Fuel Moisture Sensor was retired on September 22, 2009. It consists of an epoxy-encapsulated electronics package. It uses Time Domain Reflectometry Technology to measure the moisture content of the 10824 10-hour Fuel Moisture Stick. The 10824 is a USFS-specified, 10-hour, ponderosa-pine dowel that is purchased as a Common Accessory (see Ordering Info).