Countersunk flat Phillips Machine Screws 304 Stainless Steel Flat Head 82 Degree M3 M4 For PCB Mounting
What is a countersunk Phillips machine screw?
It is a machine screw with a flat top cone shaped head and a cross shaped Phillips recess. The head is designed to sit flush with or below the work surface. The Phillips drive gives you good tool centering and moderate torque transfer.
Installation guide – three key steps
Drill a pilot hole for the threaded portion. The hole diameter should match the screw's thread size. Use the correct drill bit for the material you are working with.
Use an 82 degree countersink bit to create the recess for the head. The countersink depth should allow the head to sit flush with the surface. Not too deep. Not too shallow. Test on scrap material first.
Use a Phillips screwdriver that matches the size of the screw. Do not use a worn bit. Apply steady pressure. Do not overtighten. Stop when the head is flush with the surface.
What is the 82 degree angle?
The head is machined to an 82 degree cone angle. This is the standard for metric countersunk screws. The angle matches standard countersink bits. When the hole is countersunk correctly, the head sits perfectly flush.
Phillips drive advantages
| Advantage | Why it matters |
|---|---|
| Self centering | The screwdriver finds the center automatically |
| Good torque transfer | Less slipping than slotted drive |
| Common tooling | Phillips screwdrivers are everywhere |
| Moderate cam out | Reduces damage to the screw head |
| Cost effective | No specialized tools required |
Head styles within this family
| Head type | Best for |
|---|---|
| Standard flat head | General countersink applications |
| Low profile flat head | Shallow countersink, thin material |
| Oval head | Countersunk with rounded top, decorative |
| Trim head | Smaller head diameter, clean appearance |
Material choices
| Material | Best for |
|---|---|
| 304 stainless steel | General corrosion protection, outdoor |
| 316 stainless steel | Marine, saltwater, chemicals |
| Brass | Non-magnetic, decorative, electronics |
| Steel with zinc plating | Cost effective, light outdoor |
| Aluminium | Lightweight, non-magnetic |
Strength grades
| Grade | Best for |
|---|---|
| Class 4.8 | Light duty, general assembly |
| Class 6.8 | Medium strength, higher loads |
| Class 8.8 | Heavy duty, industrial |
| Class 10.9 | High strength, demanding |
| Class 12.9 | Maximum strength, critical |
Thread types
| Thread | When to use |
|---|---|
| Coarse thread | Standard, most common |
| Fine thread | Thin materials, better holding |
| Machine thread | Pre tapped holes or nuts |
Where are they used?
- Electronics enclosures – flush mounted screws
- PCB mounting – secure board attachment
- Instrument panels – clean finished appearance
- Machinery covers – safety guards
- Automotive interiors – trim and panels
- Furniture – hidden fasteners
- Signage – surface mount
Quality
ISO 9001 and ISO 10012 certified. Every batch inspected. Countersink angle checked. Thread gauging. Hardness testing.
- 82 degree countersunk head – sits flush with surface
- Phillips cross recess drive – self centering, good torque
- Flat head, oval head, low profile styles
- 304 SS, 316 SS, brass, zinc plated steel, aluminium
- Metric M2 to M6, Class 4.8 to 12.9
- Coarse and fine thread options
FAQ
YH Fastener has been manufacturing precision fasteners since 1998. Our range includes countersunk Phillips machine screws, self tapping screws, shoulder screws, and custom fasteners. ISO 9001 and ISO 10012 certified. Every batch inspected. Factory direct. Ship to 60+ countries.
