DECLARE @secs int
SET @secs = 6*60*60 + 9*60 + 02
select CONVERT(varchar(10), dateadd(ss, @secs, 0) , 108) 

>DATEDIFF worked perfectly, thank you. Is there a way to show it as 0:09:02 to show 9 minutes and 2 seconds difference? I looked at the CONVERT function and it doesn't seem to do what I want it to.