Qualitek 6040 solder wire with nc600e flux qualitek nc600 60 070 2 5 a flux cored solder wire made from an alloy consisting of 60 tin and 40 lead the nc600e flux is made from synthetically refined resin combined with a highly effective activator qualitek tin lead solder wire 6040 nc600 flux 22 071mm 500g reel