Is there supposed to be a note inside a return?

[efay4448]

The first time I returned something, I did it all from my ebay:  the shipping label was on half the paper that printed out.  The other half said to enclose that part in the box I was returning.  This time, evidentally, I took a left at Albuqurque because I couldn't for the life of me find a way to print a return label from ebay.  Finally opened an account with the USPS and did it that way.  But what about the little piece of paper that goes back to the seller in the box?  Is that NECESSARY?  Can I just return it with no note?  Help me Obi Wan.