All Roo's come with the slideout travel bars. I used mine every trip. They only take 2 minutes to install. I assigned that task to one of my DSs.
You may be able to order them from Forest River if the original owner didn't give them to you. The 21SS has a large, heavy slide so I'd recommend getting them.
2011 Rockwood Signature Ultra Lite 8293SS, 12K Equal-i-zer
2016 Ford F-250 XLT SuperCrew, 6.2L, 4x4, 6'9" bed, 3.73
2010 Rockwood Roo 23SS (2012 - 2014)
2009 Ford F-150 XLT SuperCrew, 5.4L, 4x4, 5'6" bed (2012 - 2016)