The Mares Cruise Backpack Roller bag gives you the ultimate bag in terms of diversity. 

This 128 litre capacity bag is plenty spacious enough for all of your dive gear, has wheels and shoulder straps ensuring it is easy to transport, then folds down into a small hand help carry bag in less than a minute. 

Super lightweight, weighing on 3kg this bag at full size measures 47 x 32 x 81cm.