This is a seven segment display that counts a specific resource. I had problems finding blueprints for this kind of display and with the help of a few youtubers, i made it. To get the display working you will want click on the arithmetic combinator that is separated from the rest.(Bottom left) you will want to connect the input of the combinator to a power pole that is connected to the whatever item you want counted. change the input value to the specified resource and add 0(oil + 0).
I by no means created this, all credit goes to:
HypnoBunny Gaming: https://www.youtube.com/watch?v=gPZU8_chH1U,
JelleWho: https://www.youtube.com/watch?v=N3JgOLIGYwI,
ANameOfMyChoice: http://imgur.com/a/dSW2i