Kester 24-6337-8807 is a no-clean flux cored wire solder. It has an Sn63Pb37 (63% Tin / 37% Lead) alloy, .020" wire diameter, #245 no-clean flux, and #50 flux core size. Kester Formula #245 was developed to complement low residue liquid fluxes being used by the electronics industry. The use of this flux results in visually acceptable assemblies without cleaning, yet soldering quality and efficiency is comparable to that obtained with mildly activated rosin flux. The flux residues left after soldering are non-corrosive, non-conductive, and do not require removal in most applications. Kester #245 is classified as ROL0 per J-STD-004 and is Bellcore GR-78 compliant. Kester 24-6337-8807 comes packaged on a 1-lb. spool.