STAINLESS STEEL HEXALOBULAR BUTTON SCREWS ISO 7380-1

Hexalobular Button Screws ISO 7380-1 — Hexalobular button screws combine the shallow, ISO 7380-1 domed head of a standard button screw with a six-lobed drive in place of the hex socket. The head geometry — diameter, dome height, bearing area — is identical to the hex socket version, so the standard governs the same low-profile shape either way; the only change is the recess, sized to accept a lobed bit rather than a hex key. That drive change matters more on a button head than it does on a cap head, because the shallow dome leaves less material depth for the recess to begin with — a hex socket in a shallow head is already working with less engagement than in a tall cap head, so the extra contact area of a hexalobular recess helps offset that shallower depth and resist cam-out, particularly under powered or repeated tightening on a production line.

Typical uses mirror plain socket button screws — guarding, enclosure panels, machine covers, and any assembly wanting a low, rounded head — but hexalobular versions are specifically worth choosing where the fastener will be driven by a powered tool rather than a hand-held Allen key, since consistent torque delivery matters more in that setting and cam-out on a shallow-recessed head is more disruptive to a production line than on a deeper cap screw socket.

Grade guidance follows the pattern for the wider button screw family: A2 is the sound default for indoor, low-corrosion assemblies, and A4 earns its higher price where the finished product meets salt air, washdown chemicals, or sustained damp — food-grade equipment covers and outdoor enclosures being the common examples. Because these are frequently specified in bulk for production assembly, getting the grade decision right at the outset avoids a costly retrofit later if the product turns out to need better corrosion resistance than A2 provides.

Size and length selection follows the same rule as any button screw: check the joint's actual load needs before assuming a larger diameter is the safe choice, and size the length for full thread engagement in the tapped material, using coarse thread unless the application specifically calls for fine.

FAQs
How do hexalobular button screws differ from hexalobular cap screws?
Both use the same hexalobular drive, but the head form differs: button screws have a shallow domed head with lower bearing area and clamp capacity, while cap screws have a taller cylindrical head suited to higher-torque, higher-load fixing.

How do hexalobular button screws differ from flanged hexalobular button screws (ISO 7380-2)?
The ISO 7380-1 version has a plain domed head with no integral flange, relying on the head diameter alone to spread load. The ISO 7380-2 flanged version adds a wider bearing collar beneath the head, spreading clamp load over a larger area without a separate washer.

What bit size is needed to drive these screws?
Hexalobular sizes are denoted by a T-number rather than a hex across-flats measurement, and the correct T-size should be checked against the screw's nominal diameter rather than assumed from a similar-looking cap screw.