YOUNG CHANG SILICONE′s Triple-insulation-wire.php (STW-B) is designed to fulfill the requirement of Class B thermal index. STW-B is the insulated winding wire having reinforced insulation complying with subclause 188.8.131.52 Annex U of IEC 60950 and subclause 184.108.40.206, Annex U of IEC. STW-B makes a merit of needing no interlayer insulation material such as insulation tape or barrier tape, thereby downsizing transformers a great deal, bringing about high efficiency and cost cutback. Easier to design environmentally friendly transformers which can be easily disassembled and recycled. It is anticipated that Young Chang Silicone′s STW-B will play a role in a widening range of fields.