Zaccaria used an unusual method of showing the match number on some of their EM games. Instead of a number lighting up on the back glass, they used an extra score unit with the numbers in red. It had a small window in the back glass, and the match was read through it at game over. It stepped from playfield scoring just like a normal match unit, but it could not be seen doing it as a metal plate covered the hole during game play. It was held against spring tension by the 26-800 coil. When the game ends, the coil releases and the spring pulls the plate clear of the window, revealing the match number.
It wasn't the best design for the job, and that coil only just has the power to do the job. If it doesn't pull the plunger in, it overheats, and as it's energised for a full game, it doesn't take many games before it burns out. The mech needs to be perfectly clean and free and the spring tension has to be set perfect for it all to work. A bit too much tension on the spring, or friction in the mechanism will stop the coil pulling the plunger in.