A code violation waiting to happen: In this case, penetrants have been punched and burned through a drywall assembly required to have a fire-resistance rating. The integrity of the drywall has been seriously compromised at the through-penetration and will be fixed with nothing but drywall mud, whereas a solidly framed opening could have been spared out and sealed in a manner preserving bounding by a speciality firestop subcontractor. Details of this nature illustrate the difference between drywall testing and certification and the compromises made in the field, which would have a very difficult time passing actual testing.The studs are made from a thin galvanized mild steel shape bended to strenghten its structure. The thickness alow the penetration of the screw to make the assemble between the board and stud easy.