A blank can include a first end panel; a first main panel joined to and extending from the first end panel; a second main panel connected to the first main panel; a second end panel joined to and extending from the second main panel; an inside end panel connected to the second main panel; and a locking tab extending from and separable from the first main panel, passable through a first opening defined between the second end panel and the inside end panel, and engageable with a locking opening separate from the first opening and defined in the blank.