To add Additional Items to a Service, use the 'Add on Products' tab in the left-hand side components.

You'll be presented with a pretty empty Item List. This first Item List is the 'Kit Lists' tab. Here you can use the 'Kit' drop-down to select a Kit Definition from a list of Standard Kit Definitions and Custom Kit Definitions that are available to the Service Account.
This can be useful if you have a Standard List prepared for popular items or if you know that the request Additional Item is in a Standard Kit. Selecting a Kit List will give you an Item Selector similar to the one used for Restocking an Asset.

The other option is to use the Search Products tab.

By default this tab will begin to load all Items in your region's Price Book. The list can be filtered by entering part of a Product Name or Product Code into the Search Box and hitting 'Enter' (or submitting on a mobile device or tablet).
This will filter the list of items down to those that match your Search Term.
You can also use the 'Category' selector to filter the Products in the list by their Product Family. The Category selector will only show categories that match products which meet the Search Term, so if you can't find a category that you expect, clear the Search Box first by deleting any text and submitting the search.

The Items in the Search List can be added to the Additional Products by using the '+ 1' button. They will then appear in the 'Selected Items' list, similar to how Assets work.

If you've sold an Additional Item to a customer and they'd like St John to track that item as an Asset, you'll have the option to create an Asset record from the Selected Items list.

Selecting the 'New Asset' button will do several things:

1. The 'Create a new Asset' modal will appear. Select 'Next' to continue to fill out the required details for the new Asset. You will have another opportunity to update the Asset before the Service is completed.
2. After creating the Asset the Required Quantity for the Item in the Selected Items list will be reduced by 1. In our example because only 1 Item was required, it was also removed from the list.

3. The newly created Asset has been added to the 'Selected Assets for Service' list. You will find it by going to the 'Service Assets' tab in the left-hand components and looking at the bottom of the list.

4. Selecting the 'Restock' button will open up the Asset details. You'll find that the Item for the new Asset has been added to the 'Selected Items' tab on the right.
If the Item in the 'Add on Products' had already been Delivered, then the Delivered Quantity will be 1. Otherwise the Delivered Quantity will be 0.

The reason why we've moved the Item from 'Add on Items' to instead be attached to the newly created Asset is to make it easier to understand how many of the 'Add on Items' have been converted to new Asset records.
Imagine if you sold 10 first-aid kits, eventually it would be difficult to remember how many of those kits you've converted to Assets.

You'll also have the opportunity to 'Mark Complete' for the new Asset, giving you an opportunity to finalise any Asset details.