TE Connectivity's flexible range of power wirewound resistors contains either wire or power oxide film elements. The SQ series resistors are wound or deposited on a fine non - alkali ceramic core, then embodied in a ceramic case and sealed with inorganic silica filler. This design provides a resistor with high insulation resistance, low surface temperature, excellent T.C.R., and entirely fire proof construction. These resistors are ideally suited to a range of areas where low cost, and efficient thermal performance are important design criteria. Metal film cores adjusted by laser spiral are used where the resistor value is above that suited to wire. Similar performance is obtained although short time overload is slightly derated.