Sales and R&D of Samsung SMT machines, printing machines, upper and lower triggers, reflow soldering, steel mesh, silicon wafers, glass, cleaning machines, parallel transfer machines, board collecting machines, cache machines, glue dispensing machines, depanel machines, plug-in machines, marking machines, and assembly line assembly automation equipment; domestic trade; operating e-commerce (if a pre-existing administrative license is involved, you must obtain a pre-existing administrative licensing document before operating); operating import and export business.