Revell's item no. 01265, the Big Boy steam locomotive comes in a soft box. The box itself is very nicely designed. Inside it you will find the 87 parts that need to be put together. They are made of good quality black plastic and they are grouped into 4 units: The main part of the locomotive and the main part of the tender are separated from other components, while all the other parts are in a plastic frame from which they need to be removed.
Inside the box there is also an instruction manual and a safety advice document. Everything in the manual is translated into several (many) languages. It contains general assembly instructions and warnings, information about the required paint colors and 41 very detailed drawings that will guide you through the steps of assembling the Big Boy locomotive. One thing that I was not happy about is that on the outside of the box only 5 colors are listed as required paints (8, 9, 91, 99, 330), but the instruction manual lets you know that you will also need colors 75, 86 and 92.
Otherwise the contents of the box is more than satisfactory. It contains everything a modeler would expect, except the accessories, of course: paint, brushes and glue.