Address Building 7-16, No.188, South 4th Ring West Road, Beijing, China Mail yangshan@const-mach.com chenyoufeng@const-mach.com liuyang@const-mach.com Phone Mr. Yang：15010377396. Mr. Chen：13801306377. Mr. Liu：15910904980. Operating hours Monday-Friday: 9am to 6pm Saturday, Sunday: Closed
