Flux Rosin has high purity, no impurities, anti-oxidation, no cleaning, and high activity. How to use:  electronic components are generally tinned. After the circuit board is scratched, the tinned components can be directly soldered with rosin core soldering. Remove the soldering iron before the rosin has evaporated. If the solder is sticky, stick with the rosin. Do not move the component until the solder is solid. Environmentally friendly and non-toxic soldering flux rosin, welding standing flux, easy to solder, bright solder joints, good insulation, making soldering more firm, no odor, enhancing solder fluidity, helping solder wettability, meeting soldering needs, and making work easier Comfortable, suitable for motherboard repair, circuit welding, home appliance repair.