Schott SF/R Series SEFUSE Thermal Cutoffs Axial - Schott SF119R1, A 121°C thermal fuse that uses an organic thermosensitive pellet inside a metal case. Features a large rated current of up to 15A 250V AC. The device contains a sliding contact, springs, and a thermal pellet inside a metal case. When the spring is compressed, firm contact between one lead and the sliding contact occurs. At normal temperatures, current flows from the lead to the sliding contact and then through the metal case to the other lead. When the ambient temperature rises to the SEFUSE operating temperature, the heat transferred through the metal case melts the thermal pellet. When the thermal pellet melts, two springs expand, moving the sliding contact away from the lead. The electrical circuit is opened by breaking contact between the sliding contact and the lead. Schott SF119R1 121°C Sefuse Axial Thermal Fuse