Within the Settings module, under the Customer Items section is the Customer Item Types. 

This is the collection of all the different types of Customer Items that have been created in Infusion.

To add a new customer Item Type, choose Add to open up the Add Customer item Type screen:

Enter in the Code and Description of this new Customer Item Type.  After these have been entered, the Custom Fields need to be defined for this Customer Item Type. Select the type of custom field using the dropdown. More Custom Fields can be added in the Item Types Custom Fields section of the Settings. 

You can add as many custom fields to a Customer Item Type as required, by selecting them in the drop down menu and then choosing the add icon.

Use Save to complete the set up.

Unlinking a custom field

Custom fields added to a Customer Item Type can be unlinked at any point by choosing Unlink.

Once unlinked, the custom field can be relinked choosing it from the Custom Field dropdown and then using Add