A leading private sewage operating firm (603903.SH)

A state-owned water operation firm in Fujian Province (603817.SH)

Natural gas pipeline construction and operation firm (833403.OC)

A leading oil service provider in China (300164.SZ)

A domestic high purity process system solution provider (603690.SH)

Offshore oil and gas development engineering designer (832547.OC)

Market leader of CTL field