• Highest activity available
• Compatible with high-temperature alloys
• Easy to clean
• Classified as ORH1 per J-STD-004

Kester OR-421 is a high-activity, water-soluble, cored wire flux. The OR-421 is more heat stable, exhibits better wetting capabilities, and has less odor than competitive products. The residues left by OR-421 are near neutral pH and therefore also less corrosive. The OR-421 is classified as ORH1 per J-STD-004. OR-421 cored solder wire can be utilized with an open torch or a soldering iron. OR-421 will solder copper as well as more difficult-to-solder materials such as brass and nickel. OR-421 can be used on pipes or tubing for applications such as refrigeration coils and heat exchangers. The heat stability of OR-421 makes it ideal for high-temperature alloys such as Sn95Sb5, Sn63Pb37, and K100LD.