The Kester 185 mildly activated rosin is classified as type ROL0 flux under IPC J-STD-004 Joint Industry Standard. Under the older MIL-F-14256, 185 was QPL approved as type RMA. This formulation consists of high quality, purified rosin to which a synergistic combination of activating agents has been incorporated. The fluxing ability of 185 flux is much greater than ordinary mildly activated rosin fluxes and approaches the activity of fully activated rosin fluxes. - 185 rosin flux represents state-of-the-art flux formulation technology. This flux has been developed for use in critical electronic applications where difficult assemblies are to be soldered, but process requirements stipulate use of mildly activated rosin flux.