🔩 M3–M10 Phillips Countersunk Machine Screws – A2 Stainless Steel, Fully Threaded (3–100mm Overall Length)
You’re bolting down a deck, installing stainless steel hinges on a boat, or assembling outdoor furniture – and you need a screw that sits flush, won’t rust, and drives easily. These M3 to M10 countersunk machine screws are made from A2 stainless steel (304), offering excellent corrosion resistance for humid, coastal, and industrial environments. The Phillips drive works with standard crosshead screwdrivers, and the flat 90° head sinks perfectly into a pre‑drilled countersink, leaving a smooth, professional surface. Available in M3, M3.5, M4, M5, M6, M8, and M10 diameters, with overall lengths from 3mm to 100mm (including the head). Fully threaded for maximum grip. Ideal for marine hardware, furniture, machinery, and general DIY.
✨ Key Features – A2 Stainless Countersunk Phillips Screws
- 🔽 Countersunk flat head (90°) – Sits flush with the surface after proper countersinking. Smooth, snag‑free finish.
- 🛡️ A2 stainless steel (304) – Excellent corrosion resistance, oxidation resistance, and heat resistance. High strength and toughness.
- 📐
Phillips drive – Standard cross recess works with common screwdrivers. Good torque transfer.
- 📏 Wide metric range M3 to M10 – M3, M3.5, M4, M5, M6, M8, M10. Covers small electronics to heavy machinery.
- 📐 Overall lengths 3–100mm (including head) – Example: M6 x 20mm means total length from top of head to tip is 20mm. Fully threaded.
- ⚙️ DIN 965H standard – Precision dimensions, consistent quality, and reliable countersink angle.
- 🔧 Widely used – Marine hardware, outdoor furniture, machinery, electronics enclosures, and general construction.
📏 Specifications – M3 to M10 Countersunk Phillips Screws (A2 Stainless)
| Thread Diameter (M) |
Thread Pitch (mm) |
Overall Length Range (mm) * |
Head Style |
Drive |
Material |
| 📐 Length measured from top of head to tip (total screw length). Fully threaded. Select exact size from dropdown. |
| M3 |
0.5 |
3, 4, 5, 6, 8, 10, 12, 16, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100
(exact availability varies) |
Countersunk / flat (90°) |
Phillips |
A2 304 Stainless Steel |
| M3.5 |
0.6 |
| M4 |
0.7 |
| M5 |
0.8 |
| M6 |
1.0 |
| M8 |
1.25 |
| M10 |
1.5 |
* Lengths are typical – exact availability may vary. Please allow minor manual measurement errors. DIN 965H standard ensures consistent head geometry.
📋 Why Choose A2 Stainless Steel Countersunk Screws?
| Property |
Benefit |
| Corrosion resistance |
Excellent – resists rust in outdoor, humid, and coastal environments. Suitable for marine‑adjacent use. |
| Strength |
High tensile strength (A2‑70 ~700 MPa). Durable for structural and mechanical fastening. |
| Flush finish |
Countersunk head sits flush – ideal for smooth surfaces, sliding mechanisms, and safety‑critical assemblies. |
| Fully threaded |
Maximum thread engagement for blind holes or through‑nut applications. |
❓ Frequently Asked Questions – Countersunk Phillips Screws
1. How do I measure the length of a countersunk screw?
For countersunk screws, the length is measured overall – from the top of the head to the tip. So an “M6 x 20mm” screw has a total length of 20mm including the head. This matches our listing.
2. Do I need to countersink the hole for these screws to sit flush?
Yes – these are true 90° countersunk screws. For a flush finish, drill a matching 90° countersink hole. Use a countersink bit slightly larger than the head diameter.
3. Are these screws fully threaded? What about longer lengths like 100mm?
Yes – all screws in this range (M3 to M10, up to 100mm) are fully threaded from under the head to the tip, giving you maximum grip in blind holes or through‑nut applications.
4. Can I use these screws outdoors? Will they rust?
A2 stainless steel (304) is highly corrosion‑resistant and suitable for outdoor use in most environments – rain, humidity, and coastal areas. For continuous saltwater immersion, consider A4 (316) stainless, but for general outdoor furniture and marine hardware, A2 is excellent.
5. What Phillips screwdriver size do I need for M3–M10?
For M3–M4: #0 or #1. M5–M6: #2. M8–M10: #2 or #3. Always use a driver that fits snugly to avoid cam‑out and head damage.
6. Can I use these screws with a nut? What size nut fits?
Yes – these are machine screws. Use standard metric nuts of the same thread size (e.g., M8 nut for M8 screw). For outdoor use, pair with stainless steel nuts.
