Link Group Code to Inventory Item Once the groups have been created, you will need to link the inventory Items to the respective group codes. Inventory Module> Configuration> Inventory Setu p Select and edit the required Inventory Item Select the required group code from the drop down list Click Save and Close. As noted in the group code setup section, this will dictate the relevant sales and cost of sales account posting when this item is processed on an invoice or credit note. Multiple reports can be generated using the inventory group code as a filter, thereby assisting in sales and inventory analysis.