It's an old long sleeved shirt that is turned into a skirt. It is useful for when you don't have a skirt that matches your outfit or you just don't have any at all and you have an old sweater that you don't wear anymore and you want to make use of it.
(the baggier the shirt, the longer the Put on T-Shirt without putting your arms in the sleeves. Tuck the sleeves into the T-Shirt. Wear your DIY no-sew dress! Could wear with an adorable sleevless jean jacket!