๐ฉ Product Overview: M2 & M3 A2 Stainless Hex Drive Flat Head Screws (Countersunk)
If you're tired of Phillips screws slipping or need a clean, flush finish for your project, these A2 (304) stainless steel hex drive flat head screws are a solid upgrade. The internal hex socket (Allen key) gives you positive engagement with no camโout, while the countersunk flat head sits perfectly flush in tapered holes โ ideal for electronics enclosures, 3D printers, furniture, and marine hardware. Available in M2 and M3 metric diameters with various lengths, they're fully threaded and made from corrosionโresistant 304 stainless. No more rust, no stripped drives โ just reliable fastening that looks professional.
โจ Why Choose A2 Stainless Hex Drive Countersunk Screws
-
A2 (304) stainless steel construction โ Excellent corrosion resistance for outdoor or humid environments. Resists rust and acid better than 201 stainless. Widely used and trusted.
-
Hex socket (Allen) drive โ Internal hex provides full contact engagement, eliminates camโout, and allows higher torque without stripping. Perfect for power tools and precision work.
-
Countersunk flat head โ 90ยฐ flat head sinks flush into countersunk holes. Leaves a smooth, snagโfree surface โ ideal for panels, machine guards, and visible assemblies.
-
Metric sizes M2 and M3 โ The most common small diameters for electronics, RC vehicles, laptops, and hobbyist projects.
-
Fully threaded, GB standard โ Threads run the entire shank length. M2x0.4 and M3x0.5 coarse pitch for maximum grip in thin materials.
-
Grade 5 strength equivalent โ Strong enough for most smallโscale structural and mechanical fastening.
-
Made in China, quality assured โ Consistent threading and clean heads. Available in various lengths (see product options).
๐ Technical Specifications โ M2 & M3 Hex Drive Countersunk Screws (A2 Stainless)
| Specification |
Details |
| Product Type |
Hex Socket Flat Head Countersunk Machine Screws |
| Material |
A2 Stainless Steel (304 / 18-8) |
| Drive Style |
Hex key (Allen) โ internal hex socket |
| Head Style |
Flat / Countersunk (90ยฐ typical) |
| System of Measurement |
Metric |
| Screw Sizes (Diameter) |
M2, M3 |
| Thread Pitch |
M2 x 0.4mm, M3 x 0.5mm (coarse) |
| Thread Type |
Fully threaded (full length from under head to tip) |
| Length |
See product options โ varies (typical range 4mmโ30mm) |
| Standard |
GB |
| Grade |
Grade 5 |
| Finish |
Natural stainless steel (unplated) |
๐ Stainless Steel Comparison โ Which Grade to Choose?
| Grade |
Corrosion Resistance |
Surface Brightness |
Best Use |
| 201 Stainless (SUS) |
Poor โ rusts with water |
Dull, blackish even when polished |
Dry indoor environments only |
| 304 Stainless (A2) |
Good โ resists corrosion & acid |
High brightness, clean finish |
Outdoor, humid, general purpose |
| 316 Stainless (A4) |
Excellent โ with molybdenum for saltwater & chemicals |
Bright, similar to 304 |
Marine, coastal, highโchloride areas |
โ FAQs โ M2/M3 Hex Drive Flat Head Screws (A2 Stainless)
๐ธ What hex key (Allen wrench) size do I need for M2 and M3?
For M2 hex socket flat head screws, use a 1.5mm hex key. For M3, use a 2mm or 2.5mm hex key (most common is 2mm). Always check fit โ a quality metric hex key set (1.5mm, 2mm, 2.5mm) will cover these.
๐ธ Are these screws fully threaded? How is length measured?
Yes โ they are fully threaded from under the head to the tip. Length is measured as total screw length including the head (standard for countersunk screws). For example, an M3 x 10mm screw is 10mm long overall from top of the flat head to the tip.
๐ธ Will A2 (304) stainless steel rust in outdoor or coastal environments?
304 stainless is highly resistant to moisture, rain, and humidity โ perfect for most outdoor use. However, in coastal areas with high salt spray or chlorides, 316 stainless (A4) is recommended. For general outdoor furniture, garden equipment, and covered marine applications, 304 performs very well.
๐ธ Can I use these screws with nuts, or are they selfโtapping?
These are machine screws โ they require a matching metric nut (M2 or M3) or a preโtapped hole. They are not selfโtapping. For best corrosion resistance, pair them with 304 stainless nuts.
๐ธ How do I identify genuine 304 stainless vs 201?
Genuine 304 has a brighter, cleaner surface and higher corrosion resistance. A simple test: 201 stainless will show rust spots quickly in humid conditions, while 304 will remain shiny. You can also use a stainless steel test solution โ no color change indicates 304.
๐ธ Are these screws magnetic?
304 stainless is generally nonโmagnetic in its annealed state, but cold forming (like thread rolling) can make it slightly magnetic. A light magnetic response is normal and does not affect corrosion resistance.
