Conventionally, Sn-Bi (tin-bismuth) solder alloys could not be used in flux cored solder products, since its hardness and low ductility. Qunwin has succeeded in developing Sn-Bi lowtemperature flux cored solder wire by fully utilizing our propitiatory processing technologies. The product enables soldering at 200℃ to make possible and is is optimal for packaging of low heat-resistant components or substrates.