Unsure Dimension

Make the steel rod ladder rungs 7/8” in diameter question mark?
We can hear them calling in the order now, “ah….make the steel rods 7/8” or there abouts… unless I change my mind… in other words, to-be-determined-later… but I have to order them now! So, please look into your crystal ball and give me the exact size that I’ll be needing.”