Such as 6-ping line is the air conditioning line or what line, 4 level, 2.. 1.5 of it, please elaborate, thank you master! The The More
This is a weak line can wear a tube, you rest assured that all right
Optical is generally used for monitoring. Video, audio and data signals. There are special switch alarm, 485 network signal. You should be talking about fiber optic transceivers.
From one to the inside to see the water, but also see
