Hi. I'm trying to show the serial number when user are going to open a RMA from a order (via RMA module).

How can I get this field? I researched and it seems serial number is in stock.move.lines or stock.production.lot but I can't see how get this from a sale.order

I found this two path, using relations, not sure if it's correct

sale.order -> mrp.production.request -> mrp.production -> stock.move.line -> LOT_NAME (field)

sale.order -> mrp.production.request -> mrp.production -> stock.move.line -> stock.production.lot -> NAME (field)

But I can't see how to get this field.

Thanks a lot