Open top containers have four walls and an open top that a removable roof can cover. They have solid walls and a door for loading and unloading cargo.  On the other hand, flat rack containers have a base and only two walls. Depending on the manufacturer, the walls can either be fixed or foldable to accommodate longer cargo.  Flat rack containers are suitable for oddly-shaped goods that won’t fit in a standard closed or open top container. Once loaded, you can secure them with lashing through the sturdy lashing rings.