Click on the image below to view it full size in an image viewer !
SmallBox.bdd: a concrete box with a redefined fixed length and the ability to contain 1 ColoredThing

The smallest of the boxes amongst the props has a side length of about 100mm, and this is indicated as the fixed default for a redefined Property length : mm = 100.

This example uses the SysML1.1 style of unit declaration where the name of the ValueType indicates the unit symbol.