There was a line of decorative trim on one end; if Rarity was holding it like it was meant to be worn, that was the bottom. He pulled it over his head and wormed his way through it, expecting to find a head-hole, but instead the whole tube was the same diameter, and taller than his body.  He held the top of it in puzzlement, until he noticed the large golden buttons on the inside.  Rarity watched him struggle to fold the top down and fasten the buttons with puzzlement.  She probably thinks I wear these all the time . . . no wonder she’s confused that I can’t figure it out.