The final bonus item in the original Pac-Man sequence is the key.
Pac-Man’s bonus symbols appear beneath the ghost house after Pac-Man eats a set number of dots. The sequence begins with a cherry and continues through strawberries, oranges, apples, melons, Galaxian flagships, and bells before reaching the key. Once the key is introduced, it becomes the recurring bonus symbol on later stages.
The key is worth 5,000 points, the highest value assigned to any standard bonus symbol in the original arcade game. This is why the key is often remembered as the game’s ultimate fruit bonus, even though it is not technically a fruit.
A common mix-up is to identify the bell or Galaxian flagship as the final item because both appear late in the sequence. They are valuable predecessors, but the key comes afterward and remains in use for the later levels.