STAINLESS STEEL PHILLIPS COUNTERSUNK SELF DRILLING DIN 7504OH

Phillips Countersunk Self Drilling DIN 7504OH — DIN 7504OH combines the same flush-finishing countersunk head used across the OZ, O, and OV variants with a Phillips cruciform recess, for jobs where the head must sit level with the surface and Phillips remains the drive type specified or available on site. As with the pan-head Phillips screw, DIN 7504MH, the cruciform recess is more prone to cam-out under power-tool torque than Pozi or hexalobular, and that matters more here because torque rises sharply as a countersunk head draws down into the material - a bit that slips at that stage can round out the recess before the screw seats fully flush. In thin sheet the head typically pulls itself flush as it drives; in thicker or harder material a pre-formed countersink may be needed to get a clean flush finish, so it's worth trial-fitting on the actual material thickness before committing to volume. Typical applications mirror the rest of the countersunk self-drilling range: cladding, ductwork, and steel or steel-to-timber fixing anywhere a proud head would interfere with an overlapping surface or finish. Point capacity has to be matched to the full thickness of material being joined - not just the visible top sheet - with length chosen to leave solid thread engagement once the point has drilled through, since forcing an undersized point to seat a flush head risks stripping the countersink rather than fixing it properly. Grade follows the same logic as the rest of the DIN 7504 range: the drilling point is usually a hardened 410/420-type martensitic stainless even where the shank is genuinely A2 or A4, because austenitic grades don't harden enough to cut steel. A2 suits most general fixing; A4 is worth the premium in coastal, washdown, or chloride-exposed settings, where its molybdenum content resists pitting corrosion notably longer than A2.

FAQs
How does it differ from DIN 7504OZ?
Same countersunk head and thread; DIN 7504OZ uses a Pozidriv recess instead of Phillips. Selection generally comes down to available driver bits and site preference.

Is there a proud-head equivalent?
Yes, DIN 7504MH, which uses the same Phillips drive on a pan head instead of a countersunk head.

Does Phillips wear faster on countersunk heads than on pan heads?
Slightly, yes - the recess sees peak torque right as a countersunk head seats flush, and high-volume fixing is where the difference in bit and recess life shows up most.