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:Pan head self tapping screw with a Phillips cross recess, full length coarse thread and a sharp gimlet point (Non-Standard)
Materials:Carbon Steel
Surface treatment:Black Zinc Plated; matte charcoal black film, thread crests showing faint bright rub marks
Head Type:Pan head, low dome, flat annular bearing face underneath, small fillet into the shank, head diameter about 2 times the thread diameter; no washer, no flange
Drive:Phillips cross recess, four tapered wings with a pointed centre; no straight slot, no hexagon socket
Thread:Coarse single-lead self tapping thread, sharp crest, full length from directly under the head; no plain shank
Point:Sharp tapered gimlet point; no drill point, no cutting slot, no flat dog point
Size:M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M14
Forming:Single-die cold heading, thread rolling, black zinc plating, sorting
Number:689
We manufacture black phillips pan head screws in carbon steel with a matte charcoal black zinc plate, a coarse self-tapping thread over the full length and a sharp gimlet point. Head, recess, point, length and the finish are taken from your drawing, and the finish is confirmed by its real name.
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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.
Black phillips pan head screws are self-tapping screws with a low domed pan head, a Phillips cross recess and a dark finish, used where a small fixing has to read as black on the finished product. The recorded item on this page is carbon steel with a matte charcoal black zinc plate, a coarse thread over the full length and a sharp gimlet point, quoted from M1 to M14 with Number 689.
Pan head. A low dome on a flat annular bearing face, with a small fillet into the shank and no flange. The head runs at about twice the thread diameter, which is the proportion that gives a defined bearing ring without a wide footprint.
Phillips recess. Four tapered wings and a pointed centre. The bit centres itself, and the wings cam out before the head tears open — a warning rather than a failure.
Coarse self-tapping thread. A single-lead thread with a sharp crest, rolled over the full length from just under the head to the point. There is no plain shank, so the whole length below the head engages.
Sharp gimlet point. A tapered point that starts in a prepared hole. It is not a drill point, so in sheet metal the hole is drilled or punched first and the point only enters it.
Matte black zinc. The recorded finish is a black zinc plate with a matte charcoal tone, and the thread crests show faint bright rub marks where the parts have touched in handling. That is what a matte plated screw looks like, and it is worth knowing before a batch is judged by its appearance alone.
The pan head and the Phillips recess are formed in one heading stroke. On the small sizes the wall between the recess and the outside of the head is only a few tenths of a millimetre, which is why the recess is formed rather than machined — a cutter at that scale would break through the side of the head.
The head diameter runs at about twice the thread diameter, and the head height is low. That combination is what lets black phillips pan head screws sit under a cover or inside a counterbore without a flange to get in the way, while still giving the bearing ring enough area to spread the load.
The thread is rolled from under the head to the point, with no plain shank. The gimlet point is formed after rolling, which is what gives it a clean taper and a lead-in that starts in the hole rather than skating across the surface.
The black zinc is applied last over the head, the recess and the thread. It adds a few microns, so the thread is gauged in the plated condition and the recess is driven with the production bit after plating. On the small sizes that check matters more than on the large ones.
The matte tone is a passivation over the zinc, not a separate coating. It is thin, and it wears at the edges first — the head rim, the recess wings and the thread crests show brighter zinc under handling. That is the rub marks the recorded part carries, and they are a sign of a matte finish rather than of a defective batch.
The family is quoted from M1 to M14, with M1, M2, M3, M4, M5, M6, M7, M8, M9, M10 and M14 in the recorded range. Custom lengths up to 2,000 mm are subject to DFM review after drawing submission; black phillips pan head screws are normally short, because the thread is holding through a panel or a board rather than clamping a stack.
| Item | How it is defined | What we control |
|---|---|---|
| Thread | Coarse single-lead self-tapping, full length | Gauged per batch after plating |
| Head diameter | About twice the thread diameter | Checked on the projector |
| Head height | Low dome over a flat bearing ring | Measured from the bearing face |
| Recess | Phillips cross | Driven with the production bit |
| Point | Sharp gimlet | Checked on the first article |
| Length | From under the head to the point | Measured on the shop plate |
| Plating | Matte black zinc | Thickness and tone checked per batch |
Length is measured from under the head, and with a full thread the usable length is the whole shank. In a joint that goes into a blind hole, the thread depth has to be at least the length minus the panel thickness, and on the small sizes a millimetre of error is a large fraction of the engagement.
The head proportion is worth checking against the clearance hole before ordering. At twice the diameter the head covers a normal clearance hole with margin; if the drawing has an oversized or slotted hole, the next size up or a washer head is the better answer rather than pushing this head beyond what it covers.
A note on naming, because it causes real confusion when a batch is inspected. In the fastener trade, dark finishes are often described as black oxide whatever they are; the recorded part on this page is black zinc with a matte charcoal passivation, not an oxide conversion film. The two look similar and behave differently.
| Feature | What it gives | What it costs |
|---|---|---|
| Black zinc | Sacrificial protection with a dark tone | A few microns; thread and recess re-checked |
| Matte passivation | Low-glare charcoal surface | Shows rub marks at the crests |
| Pan head | Defined bearing ring, low profile | No flange, so no extra bearing area |
| Phillips recess | Standard bit, cams out before damage | Recess wears first on a dark finish |
| Coarse thread | Grip in soft materials | Lower pull-out in hard thin sheet |
The difference between zinc and oxide is what happens at a scratch. A black oxide film is a conversion layer on the steel, so a scratch exposes bare steel; the zinc is a layer over the steel, so a scratch exposes zinc and the steel is still protected. For a small screw handled by fingers and cleaned with a cloth, that is the practical difference between a mark and a rust stain.
The matte tone is chosen for appearance, not for protection. A glossy black plate catches a light and reads as a bright dot; a matte one does not. On black phillips pan head screws used on audio, instrument and equipment panels, that is the reason for the finish — and the reason the faint rub marks on the crests are acceptable rather than a rejection.
The recorded finish is a black zinc plate with a matte charcoal passivation, applied over the whole part after the thread is rolled. There is no oil on the parts as recorded, which keeps the tone even and the recess clean.
| Finish | How it protects | Effect on thread and recess | Typical use |
|---|---|---|---|
| Matte black zinc | Sacrificial zinc, matte passivation | A few microns; gauged after | Low-glare panels and equipment |
| Bright black zinc | Zinc with a glossy passivation | A few microns; recess re-checked | Consumer hardware |
| Black oxide | Thin conversion film, oiled | Almost no change | Dry indoor assemblies |
| Black nickel | Hard dark deposit | Thicker; recess re-checked | Visible decorative heads |
| Black Dacromet | Zinc-aluminium flake layer, cured | Thin film; thread re-checked | Outdoor and wet assemblies |
The recess is where plating causes a functional problem. Every micron narrows the cross, and on an M2 or M3 head a few microns is enough to make the bit tight. That is why the first article is driven with the production bit after plating and why the plating range is quoted on the drawing rather than left to the line.
Where the joint is outdoors, black zinc is the wrong answer even though it is better than oxide. A black Dacromet or a stainless version of the same head is what that service actually needs, and on black phillips pan head screws the drawing should name the environment as well as the finish.
Three applications where a small dark self-tapping screw is the right fixing:
| Where it sits | The screw closes a housing or fixes an internal bracket on a product with a black shell, at sizes down to M1.6 and M2. |
| When it goes wrong | A bright screw shows through a vent or a gap, and a glossy head reads as a highlight on camera. |
| Why it happens | The housing is thin, the fixing is small, and the assembly is handled. |
| What we control | Head diameter and recess checked on the magnified first article, thread gauged after plating. |
| Where it sits | The screw fixes a bracket or a cover where the head sits on a dark painted or powder-coated face and no washer is wanted. |
| When it goes wrong | A head without a flange pull into soft material, and a bright head breaks the finish. |
| Why it happens | The face is dark, the material is board or sheet, and the fixing is in reach. |
| What we control | Point form checked against the material sample, head diameter against the face. |
| Where it sits | The screw closes a cover or fixes a terminal cover inside a dark enclosure where the fixing is seen when the panel is opened. |
| When it goes wrong | A plated screw that rusts at the recess leaves a stain inside the enclosure, and a recess that rounds slows every service. |
| Why it happens | The enclosure is dark, the joint is serviced, and the fixing is small. |
| What we control | Recess driven with the production bit, plating thickness recorded per batch. |
Four reasons that matter on a small dark screw, each tied to what the drawing has to prove:
|
Finish called by its real name
The finish on the drawing is matched to what is actually applied, so a part specified as black oxide is not supplied as black zinc or the reverse. Basis: Finish named on the drawing and confirmed on the certificate. |
Head, thread and finish in one route
The pan head and the recess are formed in one stroke, the thread is rolled to a gimlet point, and the black zinc is applied after rolling. Basis: One route from wire to plated screw. |
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Recess and thread checked after plating
The recess is driven with the production bit and the thread is gauged in the plated condition, because the deposit changes both. Basis: First article checked after plating. |
First article to repeat production
Repeat orders are checked against the first article, which records the drawing revision, wire heat, die set, thread roll and plating. Basis: First article signed off before the batch is released. |
Shi Shi Tong forms these black phillips pan head screws on a single-die header that upsets the pan head and the Phillips recess in one stroke, rolls the coarse thread over the full length to a gimlet point and finishes the parts in matte black zinc. The first part of every run is measured on the head, gauged on the thread in its plated condition and driven into a sample of the material, before the batch continues.
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At the small sizes the plating is the operation that most often goes wrong. A deposit that is right on an M6 thread can close a recess on an M2 head, and the screw then fails on the assembly line rather than at goods-in. The recess is therefore checked after plating on every first article, and the plating range is quoted rather than assumed.
What decides whether black phillips pan head screws pass is the head, the recess, the thread, the point and the plating. The inspection agreement covers those, and the criteria come from the drawing.
Head profile on the projector |
Thread gauged after plating |
Hardness testing against the property class |
Salt-spray testing of the black zinc plate |
The recess is checked with the bit and inspected for bright zinc on the wings. That bright mark is the earliest sign the recess is too tight after plating, and it appears before the head strips — on a dark cosmetic screw it is also the first thing a customer notices.
The tone is checked against a retained sample, because matte black varies between tanks more than gloss black does. The rub marks at the crests are expected and are not a rejection; an uneven patch of tone across the flange or a blotchy head is.
Every shipment of black phillips pan head screws is traceable to the wire it was made from and to the plating batch. The grade and heat number are recorded on the material certificate supplied with the parts, the plating type and thickness are recorded per batch, 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 material or the plating. The documents carry the drawing revision and the batch number, so the paperwork can be matched to the parts.
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 dark finish the first article is approved as a colour sample as well as a dimension sample, because tone is part of the specification. Buyers visit during the process to review samples and to see how the heads are formed.
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8,678+
customers served
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87%
of orders from repeat customers
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56%
of orders through referrals
|
89
countries and regions shipped to
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Buyers and quality engineers visit for sample review, process discussion and supplier audits; the visit is arranged around production so the header and the plating 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 recorded part is black zinc with a matte charcoal passivation. Dark finishes are often called black oxide in the trade, but the two behave differently at a scratch.
Oxide is a film on the steel, so a scratch exposes bare steel. Zinc is a layer over it, so a scratch exposes zinc and the steel is still protected.
The passivation is thin and wears where parts touch. On a matte plated screw that is normal, not a defect.
The matte passivation goes first at the head rim and the recess wings, leaving brighter zinc. The protection remains; the tone changes.
A sharp gimlet point for timber, board and plastics. In sheet metal the hole is drilled first; the point enters it rather than making it.
Thread size and pitch, head diameter and height, recess size, point form, length and datum, the finish by its real name, and the panel material.
How a black phillips pan head screw project runs from drawing to repeat delivery:
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1
Send the drawing or sample
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→ |
2
Finish and head review
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→ |
3
First article driven and matched to the sample
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→ |
4
Batch production and repeat orders
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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 pitch, head diameter and height, recess size, point form, length and datum, the finish by its real name, and the material being joined.
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Thread and pitch
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Head diameter and height
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Recess size
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Point form
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Length and datum
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Finish
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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
