Description: 1. Conductor: anneal bare copper; conductor line diameter: 1.00mm, 1.13mm; 2. Pairs: usually 2 pairs. 3. Insulated single line: solid polyolefin insulated single line. The insulated lines are separated by 10 colors according to the standard requirements. 4. Layer: the shielding layer is covered by the low density polyethlene film which contains the 2.5 ± 0.5% carbon black in it, thus formed a good damproof layer.