Wave Soldering Flux Series #2212 is designed to meet current no-clean and historic QQ-S-571F flux specifications. These fluxes are particularly effective for soldering large and thick circuit boards or for selective soldering operations where long heat profiles are required. The greater solids content retains activity longer through the soldering cycle and also helps to ensure greater surface insulation resistance and overall reliability. The residue left by Wave Soldering Flux Series #2212 is hard, non-hygroscopic, non-tacky, and transparent. While it is not necessary to remove the residue, it can be cleaned from circuit boards and fixtures using a saponifier or common flux residue removers.