Superior No. 30 soldering flux is a water-based, organic acid (OA) flux with fully water-soluble post-solder residues. The OA Amino Acid/Halide activator begins oxide removal at room temperature making it an excellent choice for Lead-Free, Tin/Lead, and Fusible alloys. All post-solder residues are water-soluble and should be cleaned off in 60°/140°F water to avoid cleanliness failures.