SKULabs supports creating multiple packages at once. This is useful for large orders where you may divide products into different boxes.
While shipping an order, look for the "Add", "Copy", and "Delete" buttons at the top of the ship window. These allow you to add a new package, duplicate the current package details into a new one, and remove the currently selected package.
Below these buttons, the Packages section allows you to choose the current package you are working on.