WS 220 REFLOW OIL is a low viscosity, non-foaming and completely water-soluble fluid for oil fusing or leveling. WS220 REFLOW OIL is stable at leveling and fusing temperatures thus minimizing carbonization. WS220 REFLOW OIL is a stabilized oil and may require some initial break in or. Alternatively, add some spent oil or some flux to hasten the break in period. WS220 works well with Hot Oil leveling machines and is effective as a dross blanket in horizontal hot air leveling machines.