... after invalidation Second:The TYPICAL APPLICATIONS of the ptc thermistor for heating1.air heating,wind warming equipment,cold and warm ari conditioner ... hair curling equipment Third:PTC HEATING CHIPS of ptc thermistor for heating1.rating voltage:6 to 48V 100 to 120V ... cooking devices,facial sauna,humidifier tec. 2)Tube heating elements for curing irons,wax warmer,glue gun,dehumidifier tec3)other shapes ...