ISO 14585-F rounded head sheet metal screw with torx (form F), ST5.5 x 22, Article number 14585F550221. Property class / material: steel, surface finish zinc plated. Rounded Head Sheet Metal Screw with Torx manufactured to ISO 14585 with ISO 1478 tapping screw thread (ST) thread, coarse pitch, fully threaded. Standard parts to the same standard, property class, dimensions and surface finish are interchangeable between manufacturers; confirm the controlling standard revision, any class-society or application approval, and the mating thread before substitution.