For some back office systems you want your customers cost centers to be appended or attached to the PO field on the order. With PO Mask you can assign a cost center to an address and have it added to the PO field of the order.
Have a look below to see it working.
Turn it on and add a cost center to an address
Add a cost center for the customer, if the don't have one.
Finally, associate that cost center to an address
Now login and see how it look on the storefront.
👍 Important: When PO Mask is enabled the cost centers are restricted to the Address. Thus, user cost center restrictions for that account won't work until you turn PO Mask off. So for each account you can chose either to use PO mask with Address cost center restrictions or to use the User restricted cost centers