Which is the only FA Cup Final to use an orange football?

The 1973 showpiece is the only FA Cup final ever to be played with an orange ball.

The 1973 FA Cup Final was the 92nd final of the FA Cup. It took place on 5 May 1973 at Wembley Stadium (celebrating its 50th anniversary in this year) and was contested between Leeds United, the previous season's winners and one of the dominant teams in English football at the time, and Sunderland, then playing in the Second Division.

In one of the biggest shocks in the history of the competition, Sunderland won 1–0 to become the first Second Division side to lift the Cup since West Bromwich Albion in 1931. It remains Sunderland's only major trophy since World War II. Sunderland's team were the only FA Cup winners of the 20th century not to field any full internationals, although some of their players were capped later.