Abstract: A tethered container of desiccant and a surrounding protective cage for entry into an enclosed space to extract moisture. The weight of the cage serves as ballast to settle the assembly to the bottom of any nonaqueous fluid in the enclosed space. In one embodiment, the cage takes the form of an elongated cylinder with perforated side walls slideably mounted on a tether cable disposed through an eye in a solid end wall at one end of the cylinder. The end of the tether cable interior of the cage is attached to the container of desiccant. Preferably, the eye is located on the longitudinal axis of the cylindrical cage to enhance mobility of the device. An access opening in a portion of the cage opposite the eye permits removal of the desiccant container from the cage by sliding the cage along the tether cable away from the desiccant container. In an alternate embodiment, the tether cable opening is selectively closeable to restrain the desiccant container or its contents.