一区免费在线,日韩精品免费一区二区夜夜嗨,久草福利,国产一区二区三区在线免费观看,久久九九又粗又硬又大又爽,午夜不卡视频,美女黄色一级片

How to distinguish indoor optical cable from color?

release:admin Browse:4500 times

Yellow represents single-mode optical cable; Orange represents multimode optical cable; Some manufacturers use blue to represent multi - mode million optical cable.