双纤双向线性倒换环 two-fiber bidirectional linear switched ring

双向光纤-同轴线 bi-directional fiber-coax ; BDFC

光纤双绞线 fiber twisted pair

混合光纤同轴双绞线 HFCT Hybrid Fiber Concentric Twisted Pair Wire ; HPF HQAD Hybrid Fiber Concentric Twisted Pair Wire

双股线光纤线 two-strand optical fiber cord

双纤维线加工 double fiber thread processing