Sandro makes this "zipper fastened cardigan," which is a nice way of saying "crewneck sweater we split down the middle and added a zipper to." Like, this is definitely not a cardigan, guys. Best case scenario: We can call this a lightweight, pocket-less jacket. But that doesn't really sound that good. Point is, you should wear this over a button down shirt because the way they styled it here—over a T-shirt all the way zipped up—is kinda suspect. Over a button-down you at least have the option to leave it open and mad flowy or to zipped up if it gets a bit chilly outside and you're concerned for the safety of your nips.