It's a conduit enclosing insulated electric wires.
这是包电线的导管。
A structural unit employed in cable, consisting of four separately insulated conductors twisted together.
电缆使用的一种结构形式，它由四根各自绝缘的导线相互绞合而成。
A type of transmission medium consisting of two insulated wire twisted together to improve its immunity to interference from other(stray) electrical signals that may otherwise corrupt the signal being transmitted.
由两根外皮绝缘的导线扭在一起组成的一种类型的传输媒体，扭在一起是为提高对可能破坏被传输信号的其它（杂散）电信号的抗扰度。
