I'm very very very new for electronics design. I have a basic electronics knowledge but I know there 's many things I don't know in electronics symbol universe. I searched for reference circuit of CM103AH and I found it but I don't know what this jack is, Is it jack with LED ? I only know that 1 - 5 is a jack.
Anyone can bring light to me what are 6, 7 and 8 ? or what is this type of jack called ?

 [![enter image description here][1]][1]


  [1]: https://i.sstatic.net/LKzOg.png