MG Chemicals Sn63 / Pb37 solder wires are formulated from a blend of 63% tin and 37% lead. Made from virgin, non-recycled metal, our flux core manufacturing process eliminates flux voids and irregular wire. It is eutectic and as such has no plastic range. Generally it flows better than the Sn60 and is the preferred alloy for rework, component attach and touch-up soldering for through-hole and surface mount applications. Sold in flux core wire and available in a wide variety of sizes, diameters and gauges, see complete list on product pages for details.