It is made of copper material, featuring uniform melting. It can effectively fill the weld seam and ensure the strength and sealing performance of the welded joint. Pre-formed into a ring structure, it is easy to install at the joint of the welded part. It is especially suitable for the brazing of circular or annular joints, enabling precise control of the welding position and the amount of solder, while reducing defects such as air holes and incomplete penetration. It is widely used in the refrigeration industry for products like refrigerators and air conditioners, as well as in the manufacturing industries of electromechanical equipment, electrical appliances and instruments. It can be applied in brazing methods such as flame brazing, high-frequency brazing and vacuum brazing, and is suitable for brazing materials including copper, copper alloys, steel, cast iron and cemented carbide.