SST and QST Split Sheath Insertion Heaters are specially designed for platen, die or mold heating applications where the holes are poorly drilled or worn through age. Independent expansion of the SST and QST when energized creates intimate contact with the wall of the hole. This increases thermal conductivity and allows the elements to be removed easily when necessary. SST and QST are constructed with Incoloy sheath for long life at sheath temperatures up to 1600°F (870°C).