Tel：
+86 13143444311
Email：sst@szsst88.com
Fax：+0086-755-27322278
Address：Building 9, First Industrial Zone, Tantou Industrial City, Songgang Street, Baoan District, Shenzhen 518105, Guangdong, China
Type:Button Head Socket Cap Screw Stainless
Materials:Stainless Steel
Surface treatment:Plain
Head Type:Button Head
Drive:Hexagon socket (Allen)
Thread:Machine thread
Point:Blunt
Forming:Single Die Heading
Size:M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M14
Number:373
We make button head socket cap screws in passivated stainless, a low domed head with a shallow hexagon and a machine thread, quoting them from M1 to M14. Head height, socket depth, thread, grade and joint torque come from your drawing, and the first article is driven at your torque.
Watch the factory video·Email sst@szsst88.com
ISO 9001:2015 · Manufacturing since 1998 · 8,678+ customers · 89 countries and regions
Made to order – there is no stock catalogue. Each part is produced to your drawing, and production starts after drawing review and first-article approval.
A button head socket cap screw is a socket screw with a shallow domed head and an internal hexagon, made here in passivated stainless. The dome keeps the fixing low and smooth, the hexagon drives it, and the machine thread runs in a tapped hole or a nut. The family is quoted from M1 to M14 with Number 373 and filed against the ISO button head form.
Button head. A shallow dome on a short wall, with a flat bearing face underneath and no edge to catch.
Hexagon socket. An internal hexagon cut into the top of the dome.
Machine thread. A rolled thread for a tapped hole or a nut, ending in a blunt chamfer.
Passivated stainless. No coating, so the socket and the dome are as cut.
The form is the ISO button head one: a dome with a defined diameter and height for each thread, a socket sized to the thread, and a bearing face that is flat rather than undercut. We quote it against the customer drawing where one exists, and against that form where the drawing gives a thread size and a length only.
A button head is the low, smooth head of the socket family: lower than a cap head, rounder than a pan, with nothing that catches a hand or a cable. That shape has a cost that is easy to miss on a drawing — the dome leaves less height above the socket, so the hexagon is shallower than on a cap head of the same thread, and the torque a button head socket cap screw will take is correspondingly lower.
On steel that limit is generous enough for most joints. On stainless it arrives sooner, because the grade has no property class and the walls of the socket are softer. A button head socket cap screw in stainless is therefore a part where the fastening torque should be written down rather than judged by feel: a key with a long arm will happily round a shallow hexagon before the joint is where it should be.
What the head buys is worth that care. The dome has no rim to cut a hand, nothing to catch a sleeve, and it sits low enough to disappear into a machined recess. On equipment that is handled, or where a moving part passes close to the surface, a button head is often the only head that will do the job without a counterbore.
The bearing face is the other half of the design. A button head has a smaller annulus than a pan head, so on a soft or thin panel it dimples sooner. That is why flanged button heads exist; where the panel is soft, the flange does the load spreading and the dome keeps the profile low.
Stainless makes the whole form usable outdoors. There is no coating to chip at the dome or to wear out of the socket, so the appearance holds and the drive stays workable; what it does not protect against is galling, which is a behaviour of the alloy rather than of the finish.
The recorded range is M1 to M14, covering M1, M2, M3, M4, M5, M6, M7, M8, M9, M10 and M14. Custom lengths up to 2,000 mm are subject to DFM review after drawing submission. For a button head socket cap screw the quotation carries head diameter and height, socket size and depth, the thread and the grade, because the head height is what bounds the socket and the socket bounds the torque.
| Item | How it is defined | What we control |
|---|---|---|
| Head | Button head, domed | Head diameter and height |
| Socket | Internal hexagon, shallow | Across flats, depth and corner condition |
| Thread | Machine thread | Pitch and length, gauged per batch |
| End | Blunt, chamfered | Chamfer cut, not deburred |
| Material | A2 stainless | Grade and heat number on the certificate |
| Finish | Passivated | Surface condition and film |
Socket depth is the number to put on the drawing rather than leave to the head standard. Two suppliers can both make a button head to the ISO form and differ in how deep they cut the hexagon, and the joint torque one will take is not the same as the other.
Head height should be quoted with the socket for the same reason. A lower dome looks better and drives worse; where the joint is tightened to a figure, the taller of the available heights is the safer specification.
Three features define this part: the dome, the shallow hexagon and the stainless body. The first keeps the fixing out of the way, the second is the drive the dome has to accommodate, and the third decides how much of that drive the material will take.
| Feature | What it gives | What it costs |
|---|---|---|
| Domed head | Nothing to catch or cut | Shallow socket |
| Small bearing ring | Low footprint | Dimples a soft panel sooner |
| Hexagon socket | Common key, good grip | Lower torque than a cap head |
| Stainless body | No coating to wear in the socket | Softer walls; galls without lubricant |
| Passivated finish | Socket as cut | Not a lubricant |
The smoothness is the reason the part exists in visible assemblies. A cap head has an edge at the top of the cylinder that catches a cloth or a hand; a button head presents a continuous curve. Where the fixing is on a surface that is touched, cleaned or passed over, that difference is felt immediately.
The shallow hexagon is the trade, and on stainless it is worth managing rather than ignoring. A torque setting, or a key of sensible length, keeps a button head socket cap screw inside its limits; a long arm and a good grip is how the corners go.
The recorded finish is passivation with no coating. On a domed head that is right: a coating would narrow the shallow hexagon, round the top of the dome and wear off the bearing ring, and all three are visible or functional. Passivation leaves the geometry as cut and lets the alloy resist corrosion on its own.
| Option | How it protects | Effect on socket and dome | Typical use |
|---|---|---|---|
| A2 stainless, passivated | Passive chromium oxide film | Socket as cut | General outdoor and indoor |
| A4 stainless, passivated | Passive film with molybdenum | Socket as cut | Coastal and chemical |
| Steel, black oxide | Conversion film, oiled | No measurable build | Internal machine parts |
| Steel, zinc plated | Sacrificial zinc | A few microns; socket re-checked | Indoor general work |
| Steel, nickel plated | Barrier deposit, bright | Decorative; wears at the socket | Visible equipment |
The choice between A2 and A4 is the one that decides service life outdoors. A2 handles ordinary exposure; A4 is the answer where chlorides are present, which on a domed head means coastal air or a washdown line where water sits on the dome and runs into the socket.
Where the joint is heavy and dry, a steel button head with a property class takes more preload, and that is the right part. The stainless version is chosen for corrosion resistance and for the look, and the two should not be confused on a drawing.
Three assemblies where a button head socket cap screw is the fixing:
| Where it sits | The screw closes a guard or a cover where a hand, a sleeve or a cable passes over the surface and an edge would catch. |
| When it goes wrong | A cap head edge snags, and a shallow hexagon rounded by an over-long key leaves nothing to turn. |
| Why it happens | The head is exposed to contact, it is low, and the joint is serviced. |
| What we control | Socket driven with the production key, first article checked in the guard. |
| Where it sits | The screw fixes a bracket or a panel where the joint is cleaned daily and a smooth, stainless head is easier to clean than an edged one. |
| When it goes wrong | Water sits on the dome and in the socket, and a plated head would rust in the socket. |
| Why it happens | The joint is wet, the head is exposed, and the surface is cleaned. |
| What we control | Grade confirmed, socket driven after passivation, salt-spray sample where required. |
| Where it sits | The screw fixes a plate where the head must be smooth, non-magnetic and free of any coating that could flake. |
| When it goes wrong | A coating that flakes contaminates, and a rough edge is a cleaning risk. |
| Why it happens | The joint is cleaned, it is inspected, and the material must be stainless. |
| What we control | Passivation record with the batch, dome and socket checked. |
Four reasons that matter on a domed socket screw, each tied to what the drawing has to prove:
|
Head height and torque agreed
The head height and the joint torque are confirmed together, because the dome leaves a shallow hexagon and the torque has to fit inside it. Basis: Head height and torque agreed. |
Head, socket and thread in one route
The dome and the hexagon are formed in one stroke, the thread is rolled and the parts are passivated in the same route. Basis: One route from wire to passivated screw. |
|
Socket driven, not just measured
The first article is driven with the production key at the joint torque, because a shallow hexagon that measures correctly can still round with a worn key. Basis: First article driven at joint torque. |
First article fixes the setting
The first article fixes the wire, the socket punch and the passivation; repeat orders are compared against that record. Basis: First article signed off before the batch is released. |
Shi Shi Tong forms these button head socket cap screws from stainless wire on single-die headers that form the dome and cut the hexagon in one stroke, rolls the machine thread to a blunt chamfered end and passivates the finished parts. The first part of every run is measured on the head and socket, driven with the production key and entered into a thread gauge before the batch continues.
|
|
Cutting a hexagon into a dome is where the part is decided. The punch has to hold a curved top while it cuts six flats to full depth, and it wears at the corners; a worn punch leaves a hexagon that looks right from above and sits shallow at the base, so the key bears on the top of the flats and rounds them at a torque the joint has taken before.
What decides whether button head socket cap screws pass is the socket, the dome, the thread and the grade. The inspection agreement covers those, and the criteria come from the drawing.
Dome and socket on the projector |
Thread gauged per batch |
Hardness checked on the wire |
Salt-spray testing of the grade |
The socket is checked across flats and for depth and driven with the production key; the head is checked for diameter, height and dome form, and the bearing face underneath for flatness. The thread is gauged per batch, and the grade is confirmed on the mill certificate rather than judged by appearance.
A salt-spray sample is run where the environment asks for it. On a domed head the socket is the place that matters, because water runs into it and because a damaged hexagon cannot be re-cut.
Every shipment of button head socket cap screws is traceable to the wire it was made from and to the passivation batch. The grade and heat number are recorded on the material certificate supplied with the parts, and the inspection records follow the criteria agreed on the drawing.
ISO 9001:2015 |
RoHS test report |
Registered trademark |
Patent: security screw and driver |
With each batch we supply the material certificate, the inspection record for the criteria on the drawing and, where it is listed, the third-party report for the grade or the passivation. The documents carry the drawing revision and the batch number, so a repeat order is made to the same socket geometry that was approved.
More than 8,678 customers in 89 countries and regions have ordered from Shi Shi Tong; 87% of orders come from repeat customers and 56% through referrals. Most projects follow the same route: drawing review, first-article approval, then batches checked against that sample. On a socket screw the first article is driven at the joint torque in the customer’s part, because the socket and the seat are the function. Buyers visit during the process to review samples and to see how the heads are formed.
|
8,678+
customers served
|
87%
of orders from repeat customers
|
56%
of orders through referrals
|
89
countries and regions shipped to
|
Buyers and quality engineers visit for sample review, process discussion and supplier audits; the visit is arranged around production so the headers and the passivation line can be seen on the day the parts run.
Customer group visit – sample review |
Customer group visit – process discussion |
Customer group visit – factory tour |
Customer visit – project kick-off |
Danish customer – drawing review |
Industry exhibition – meeting customers |
The dome leaves less material above the socket, so the hexagon is shallower. The drive, not the thread, is usually what limits the joint.
The bearing ring is smaller than a pan head. On plastic or thin sheet a flanged button head spreads the load without adding height.
For general exposure, yes. For coastal air or washdown, A4 is the grade to specify.
A shallow hexagon with a long key or a worn key. On stainless the walls are softer, so the torque has to be set rather than felt.
The head needs a flat seat, but the low dome also suits a simple flat face without a deep counterbore, which is one reason it is used on thin panels.
Thread size and length, head diameter and height, socket size and depth, the grade, and the torque the joint will use.
How a button head socket cap screw project runs from drawing to repeat delivery:
|
1
Send the drawing and the clearance it fits
|
→ |
2
Head height, socket and torque agreed
|
→ |
3
First article driven at your joint torque
|
→ |
4
Batch production and repeat orders
|
Each step is confirmed with you before the next one starts; the drawing revision from the first article is what repeat orders are checked against.
For a quotation, send the drawing with the thread size and length, the head diameter and height, the socket size and depth, the grade and the joint torque.
|
Thread size
|
Length
|
Head diameter
|
|
Head height
|
Socket size
|
Joint torque
|
Sending a drawing? The form below does not take attachments. Email the PDF, DXF or STEP file to sst@szsst88.com with the part name and quantity in the subject line – the drawing is reviewed and a quotation follows.
+86 13143444311
sst@szsst88.com
