Often referred to as FIST (Fiber in Steel Tube) or FIMT (Fiber in Metal Tube), AFL is the inventor and owner of placing optical fibers into stainless-steel tubes and offers a wide variety of tube sizes and fiber counts. Applicable for use in umbilical cables, downhole cables for oil and gas rigs, towed arrays, high-temperature cables, sensor cables and OPGW, the Stainless-Steel Fiber Optic Tube preserves each fiber from environmental degradation with both the hermetically sealed tube and an inner filling of thixotropic gel. Users also have the option of encapsulating the stainless-steel tube in one of six jacket polymers to best suit their specifications.