Alloy Steel Low Head Socket Cap Screws

Sometimes the problem isn't the space around the screw — it's the space above it. A slide passes over the mounting surface, a panel closes against it, a housing sits two millimeters proud of where a standard cap screw head would reach. The low head socket cap screw is built for exactly that height budget: the same cylindrical head and internal hex drive as a standard socket head cap screw, with the head height cut roughly in half. Robotics, automation equipment, inspection fixtures, packaging machinery, machine guarding, compact assemblies — anywhere the design stacks components tightly in the vertical direction, this is the screw that fits under the lid.

What makes it the practical answer — rather than just the short answer — is what it doesn't require. A flat head screw also gets out of the way, but it demands an 82° countersink machined into the part. A low head screw works in a plain clearance hole or a shallow counterbore, with a flat bearing surface under the head doing normal cap-screw duty. That makes it the natural retrofit: when a design change or a repair puts something new in the flight path of an existing screw head, a low head screw threads into the same tapped hole with no re-machining at all — same thread, half the altitude. Machine builders keep them on hand for precisely those mid-life design collisions.

The honest trade is stamped into the geometry: half the head height means a shallower hex socket taking a smaller key, so a low head screw accepts less installation torque and delivers less clamping capability than a standard socket head cap screw of the same diameter. It's a clearance solution, not a strength upgrade — select it where headroom governs, keep the full-height screw where preload governs, and never swap one for the other without checking which of those is actually in charge of the joint.

Cold Headers supplies alloy steel low head socket cap screws in a range of inch thread sizes and lengths, including uncommon and difficult-to-source configurations — low heads are a thin-stock item industry-wide, which is exactly why we carry them. Individual product pages list exact thread size, length, head diameter, head height, and hex socket size so the clearance check takes seconds. If the size you need isn't shown, there's a good chance we can quote or supply it.

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.