80-4-5 is a wick size #4 blue. It has the fastest wicking action, but rosin flux leaves behind residues that should be removed with a flux remover. Flux-Off Rosin flux remover is an ideal choice for your cleaning process. It offers the state of the art in desoldering technology. Soder-Wick is designed for today’s heat sensitive electronic components using lighter mass, pure copper braid construction that allows for better thermal conductivity, even at low temperatures. Soder-Wick responds faster than conventional desoldering braids thereby minimizing overheating and preventing PCB damage.