The registration office of the company is the yishan city data authority, whose legal representative is zhang zhang zhang zhang; the professional work of construction (projects subject to legal authorization and subject to the approval of the relevant authorities for the execution of their activities, depending on the outcome of the approval); general projects: sale of machinery; development of mechanical equipment; processing of mechanical parts, parts and components; manufacture of general-purpose equipment (other than special equipment); installation services; repair of general-purpose equipment; manufacture of specialized equipment for environmental protection; sale of specialized equipment for environmental protection; sewage treatment and reuse; water pollution prevention and treatment services; industrial engineering services; repair of instrumentation; sale of instrumentation forms (in addition to projects subject to legal authorization)