If a flux contains halogens, it is usually higher activated than a halogen-free flux. Activated fluxes containing halogens are usually distinguished during the soldering process by better wetting. Halogen-free fluxes and their residues are usually considered as significantly less susceptible to corrosion on the solder product. This is usually only correct at first glance. The general conditions must always be considered precisely for the "Halogenated Yes/No" question. Many soldering methods do not need any halogenated activators; for some solder processes, this activator group is very helpful or even makes soft soldering possible at all.