Self-Drilling Screws DIN 7504-K / ISO 15480

Self-Drilling Screws with a hexagon washer head are drilling fasteners with a hardened drill point and tapping screw thread. The drill point penetrates suitable metal substrates while the thread forms the mating thread during installation, allowing drilling and fastening in one operation. The washer head provides a larger bearing surface than a conventional hexagon head and is suited to applications where the screw must clamp sheet material securely.

This product configuration is commonly identified as DIN 7504-K, featuring a hexagon head with a pressed-on washer. DIN 7504 has been withdrawn as a DIN standard, but DIN 7504-K remains a widely used commercial and procurement designation. The corresponding current international standard is ISO 15480, which covers hexagon washer head drilling screws with tapping screw thread.

These self-drilling screws are commonly used for fastening sheet metal, steel profiles, roofing and wall cladding components, HVAC assemblies, metal enclosures, and other light metal construction applications. The integrated drill point eliminates the need for a separately drilled pilot hole when the substrate and screw drilling capacity are compatible. Selection should consider material thickness, substrate hardness, drilling capacity, screw diameter, length, and corrosion conditions.

Standard ISO 15480 sizes range from ST2.9 to ST6.3. Common commercial DIN 7504-K sizes include ST3.5, ST3.9, ST4.2, ST4.8, ST5.5, and ST6.3, depending on the supplied specification.