Advice for packaging

I’m going to sell apparel in 50 pieces. Each compressed plastic bag has 10 pieces. So my listing is going to be 5 bags. For my FBA label, how would I label it? Am I going to need a box that fits these 5 bags, and then just label the box? Or do I label each bag? I am only selling by packs of 50.

If I label the box, is Amazon going to repack the items in a different box?