fx-115ES Plus 2nd edition keyboard.

[rprosperi]

Many calculator models (of all brands) are specifically designed with the ON/Power key recessed, with the goal being to minimize accidental power-on when carrying the unit around (in a backpack, pocket, etc.). The idea is if the unit presses up against something hard, other keys will interfere with the ON key being pressed, thus preventing accidental power-on, and associated unintentional battery drain, clearing of numbers, etc. The concept goes back to earlier days when battery life was far shorter than today's ultra low-power designs that get months of use from a single coin cell.