The tapered plug at the top is used to support accessories such as the Racing Ball (part # WI-N141) and the Electric Whirl (part # WI-N124IS). The clip under the male plug can be used to hang the Lightning Plate (part # WI-N139) or to attach a ground lead.
Picture shows Insulating Stand with a part sold separately. You can order the Racing Ball by it’s part # WI-N141.
NOTE: This item is an accessory to item # WI-N100V