Floating Mailboxes to Deliver People

Date: 3/6/2018

There were these things shaped like large mailboxes that floated on water that would "deliver" people that fit inside of them. There was a specific name for them in my dream, but now I can't remember what it was. They were open on one or both ends and people had to bend their bodies in a way that looked really uncomfortable to fit inside, and yet for some reason people liked to float in them as a leisure activity. As I was looking at someone floating in a mailbox on a sunny day, I was talking with another person about how I didn't understand how people could enjoy floating in those things, because it looked so uncomfortable. They said that they didn't understand it either.