Phillips flat countersunk head self-drilling screws form H, with ribs and wings
Headform Countersunk with ribs
Drive Cross recess H (Phillips)
Thread fully threaded
Material execution case-hardened
Surface zinc plated blue
Hardness 560 HV
C. Metal substructure
1. The wings behind the drill head, ream up a clearance hole in the timber, which is of larger diameter than the screw thread.
2. The wings are designed to shear off as they strike the substructure.
3. The screw drills its own core hole into the substructure and forms a thread so that the timber will be fastened to the substructure. The ribs under the head trimming the drilled hole for a clean countersink.
Quenched and tempered fasteners ≥ 360 HV and tempered case-hardened fasteners with electroplated coatings: Susceptible to hydrogen embrittlement!
Further notice to residual risks can be found in the introduction section.