Vintage shift dress (70s)

Very cute vintage (I think 70s) shift dress. T-shirt style, no stretch but very loose fit. Button closure at the back, has a hole next to it shown in closeup photo. Would assume a size S-M, again as it is meant to be a very loose fit. For reference I'm between a size 6-8, bust 34" I wouldn't go too much bigger than that. Slight high low design with shorter front, longer back. Very minimal.