Just those two. Even if you fill the bags up to their maximum limit you won't get enough of a difference in the two sides to level your rig in a pad that is sloped.
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2012 Sunseeker 3170DS (2016-Present)
2014 Hyundai Elantra (TOAD)
Acme EZ-Tow Tow Dolly
2011 Heartland Edge M22 (2015-2016)
2005 Ram 2500 Quad Cab, Short Bed (2015-2016)
2006 Ford F150 Quad Cab, Short Bed (2015)