Looking for this modification

[whsports]

Hey guys back in vbulletin 3 i used to have a modification that allowed a user to make a multiple page thread. For instance they would start a new thread and they would write their content, then they could press add new page and write more. There was an index box displayed that allowed users to click on the page they wanted to view. In case this isnt clear i tried to draw the pic on paint.

http://prntscr.com/4js88g

If someone could tell me what the add on was named, or can remake it for vbulletin 4 please post below.