What is the difference between the two-part invoice and the three-part invoice for manual invoicing?

The difference between the triple-part unified invoice and the two-part unified invoice is mainly that the triple-part invoice has an additional stub copy compared to the receipt copy and deduction copy of the two-part invoice, so that the buyer with the same company bank number can use it as a stub. Use. The simplest difference is that one can be unified and the other cannot be unified, because in manual invoices, only triple invoices have an extra line, and the unified invoice format allows you to fill in it.