These fluxes performed very well and cleaned up easily. They cost no more that their hazardous counterparts containing fluorides, chlorides, and other harmful ingredients. Or so it would seem. Supersafe flux which works as advertised. I've tried liquid fluxes before, but none impressed me enough to give up using rosin core solder until I came across this product .
Solder joints look great and are more quickly obtained.
If you find soldering difficult, try this liquid flux. You are not left with a residue which contributes to cold solder joints. You will find the solder flows completely over your joint. Quicker soldering means less likelihood of melting ties. I use their gel, which is more like a syrup than a paste, for soldering to HO track.