Best Solder Paste Sn99%,Cu0.7%,Ag0.3% Lead-free 10cc BST-706 Rosin flux is used to facilitate soldering. It cleans and prevents metal oxidation which allows solder to create strong, long lasting mechanical and electrical bonds. It also acts as a wetting agent, increasing the flow of solder and the efficiency of the soldering process. Perfect for mobile phones, PC cards and other sophisticated electronic chip-level flux welding. Specifications Product:BST-706 Melting point:138? Volume:10cc Weight:38g Ingredients:Sn99%,Cu0.7%,Ag0.3%