How to display batch number on purchase order

How to show batch number on purchase order?

I too have the same questions. I am trying to purchase an item that has a Batch number mandatory. The Batch numbers are manual but not sure how to add the batch number and where?

@erpnext Pl help as I am evaluating this product, Manual batch number and Quantity reservation on Sales order by batch number is an important factor for us to decide for one of my clients.