We scored this absurdly rare 2nd version Campy headset, and are sending it off to Ebay in about a week. Take a look at the rounded top nut, center line through the cups, and the unique crown race. 1958 was the only year for the cup center lines. See the chart from Hiroshi Ichikawa below for I.D.'s on 1950's Campagnolo headsets.
|Races||O-Ring (piano wire?)||O-Ring (plastic)||none||none||none|