Exhibit 21.1

List of Subsidiaries

Subsidiary	Jurisdiction of incorporation or organization
ZK Pipe Industry Co. Ltd.	Hong Kong SAR
Wenzhou Weijia Pipeline Development Co., Ltd.	People’s Republic of China
Zhejiang Zhengkang Industrial Co. Ltd.	People’s Republic of China
Wenzhou Zhengfeng Industry and Trade Co. Ltd.	People’s Republic of China
XSigma Corporation	British Virgin Islands