Why do some over/unders just have a "u" or an "o" next to them rather than "o/u"?

Question

I was looking at the Vegas.com sports lines and I noticed that some of the over/unders are listed in this format: "8o/u", while others just say "8u" or "8o". What's up with that?

Answer 1

Sometimes what happens is the sportsbook will also list the favored total's odds such as; Boston / Tampa Bay 9.5O -115  This would also indicate the Under would pay -105 on a standard .20 line.

Answer 2

It's just a way of saying the same thing but in a different way.  The over/under in this case would still be 8 for this particular site's line.