An Exacta consists of picking two runners to place first and second in the correct order. This can be 'Boxed' which will capture both outcomes or 'Standout' which you will need to pick the exact places.
Exacta:
Exacta bets require the selections to finish in 1st and 2nd place, in correct order, to be successful.
Boxed Exacta:
Boxed Exacta bets require any of the selections to finish in 1st and 2nd place, in any order, to be successful.
If a selected runner is declared a "non-runner" or scratched after the wager is confirmed, wagers will be refunded on every combination which includes the scratched runner and the combination stands and the wager re-calculated without the scratched runner.