self-tapping steel screw for aluminum profilesThe grade is 10.9 for this screw and it is M7 with a length of 25mmThe head diameter is 17.5mmS12X30 self-tapping steel screw for aluminum profilesThis bolt is steel made with zinc plated surface, the height of the head is 5.8mmsteel self-tapping screw for connecting aluminum profilesS8X25 made of steel with a grade 10.9