Kester 977 is an organic water-soluble, water- based, no-clean chemistry for high quality soldering of electronic circuit board assemblies. Designed for wave soldering applications, Kester 977 provides good wetting on most surface finishes. The flux was specifically designed to reduce bridging, which is commonly associated with VOC -free no-clean fluxes. Kester 977 has excellent soldering properties for improved productivity without sacrificing reliability of the assembly. The flux leaves bright shiny solder joints and will not attack properly cured solder masks or FR-4 Epoxy-Glass laminate. The minimal amount of residue remaining after soldering is non-conductive, non-corrosive and need not be removed. The residues left after soldering will not interfere with in-circuit testing. Kester 977 is not detrimental to the Surface Insulation Resistance (SIR) of the soldered assembly.