A top sizer clip according to one embodiment for use with a garment hanger includes a body having a pair of side walls and end walls joined to and extending between the side walls. The body includes a top wall that is joined to upper edges of the side walls and end walls. The top wall partially encloses the body so as to create a hollow body structure that includes an interior compartment defined by the end walls, side walls, and top wall. The top wall includes an opening formed therethrough for receiving a hook member of the hanger. The opening is defined by a pair of opposing first edges and a pair of opposing second side edges that extend between the first edges. The clip also includes a pair of slots being formed along the first edges and extending toward the end walls. The second edges include a pair of interference sections (detents) where a distance between the second edges is at a minimum.