Liquid Pine 30ML Product Introduction: Pine is a catalyst that makes the welding process easier because when heated, the resin decomposes an acidic substance with the surface bleaching properties to be welded. Pine resin also reduces the surface tension of solder tin, thus helping solder to stick to the weld smoother. Pine resin also works to make tin wet, stick to the welding surface, help welds isolate from the surrounding environment such as temperature, oxygen, humidity... User manual: You can apply a layer of liquid resin on the surface to be welded isolated from the surrounding environment such as temperature, oxygen, humidity...