In the SB103 column I added the picture of Hello, Etr. What do the 12/8/10 intervals in the 40fi10/12/8/10 expression mean, I don't understand how to apply it? I guess it's because it has double stirrups, but I couldn't understand it, I would appreciate it if you could explain it. Likewise, I did not understand the stirrups of the SB104 column in the second picture, thank you...