Stainless steel tube OPGW: stainless steel tube is hermetically sealed by seamless welding. The tube is filled with water resistant gel. This tube provides complete protection to the fibers from longitudinal and lateral water/moisture ingress. The interstices in between the stainless steel tube and the metallic wires are filled with anti-corrosive grease for protection from corrosion.

Al-covered stainless steel tube OPGW: optical fibers are placed in a hermetically sealed stainless steel tube covered with aluminum layer forms an optical unit. The central al-covered steel tube is surrounded by single or double layers of metallic wires. Good anti-corrosion performance well suited for highly corrosive environment without requiring the use of anti-corrosive grease.

Aluminum tube OPGW: optical fibers are placed loosely in plastic tubes embedded in a hermetically sealed aluminum tube. The aluminum tube is surrounded by single or double layers of metallic wires. Material and structure are uniform with good resistance to corrosion.