Though Natasha has done her best to drag Steve’s wardrobe into the 21st century, Tony still mocks his “Grandpa” clothing. So Steve gave Tony a pair of argyle socks. Tony tried to give them back; Steve refused to accept them. Tony hid the socks in Steve’s underwear drawer. Steve hid them in the boot of Tony’s Iron Man suit. At this point, everyone in the Tower has been the recipient of the argyle socks at least once. They were last seen in Clint’s possession.