Where is the place where Haikou buys the nano invisible anti-theft net?

Chengxi building materials market. Inquiring Baidu map, I know that in the building materials market in the west of Haikou City, there are also nano-invisible anti-theft nets. It is a building materials shop specializing in production, operation and sales, with a complete range and good quality. Haikou, also known as "Coconut City", is the capital of Hainan Province, the fulcrum city of the national "Belt and Road Initiative" and the core city of China (Hainan) Pilot Free Trade Zone (Port).