Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <dhmccauley-at-spacecatlighting-dot-com> I am selling four (4) two inch diameter aluminum corona balls with 1/4"-20 thread. These are available on ebay at: http://cgi.ebay-dot-com/ws/eBayISAPI.dll?ViewItem&item=1920701338