Many round-pronged plugs may not fit securely into outlets, leaving a portion of the prong exposed, which can be dangerous for tiny children. Therefore, it is advisable to use flat-pronged plugs with holes if you have little children.

Manufacturers often use the two holes in the prongs to affix seals, which helps customers distinguish between new and old items.

Furthermore, albeit small, these two circular holes enable producers to save a substantial quantity of steel, particularly during large manufacturing procedures.