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Home / Screws / Black 304 Stainless Steel Countersunk Hex Socket Screws Flat Head Bolts Flat Cup M2.5 M3 M4 M5 M6 M8 M10mm

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Screws
Origin -
Material 304 Stainless Steel
Finish Black Oxide Coated
Head Style Flat Head (Countersunk)
Drive Type Hex Socket (Allen)
Thread Standard Metric Coarse
Available Sizes M2.5, M3, M4, M5, M6, M8, M10
Corrosion Resistance High (Suitable for Indoor/Outdoor)
Tensile Strength Standard Grade A2-70
Application Machinery, Electronics, Furniture Assembly
Package Content Assorted Kit with Storage Box

6 reviews

A

Anonymous

Mar 31, 2026

Rating: 5/5

Professional quality

I use these for repairing small appliances. The countersunk head sits perfectly flush, and the black finish matches modern appliance designs beautifully. Will buy again.

A

Anonymous

Mar 27, 2026

Rating: 5/5

Essential for marine repairs

Used these to repair a fixture on my boat. The 304 stainless steel holds up well against salt spray, and the black coating adds a nice aesthetic touch without compromising durability.

A

Anonymous

Mar 16, 2026

Rating: 4/5

Good value, slight color variation

Overall very happy with the purchase. The threads are clean and cut well. There is a very slight variation in the black finish between batches, but it's barely noticeable once installed.

A

Anonymous

Mar 09, 2026

Rating: 5/5

Exactly as described

Fast shipping and the assortment box is very organized. Having multiple sizes in one kit saved me a trip to the hardware store. Highly recommended for DIY enthusiasts.

A

Anonymous

Mar 02, 2026

Rating: 4/5

Solid hardware

Strong screws that don't bend easily. I used the M5 and M6 sizes for assembling a workbench. The only reason for 4 stars is that I wished there were more M4 screws in the pack.

A

Anonymous

Mar 02, 2026

Rating: 5/5

Perfect fit for my project

These black screws look fantastic on my custom PC build. The hex socket is precise and didn't strip even when tightened firmly. Great quality stainless steel.

5 FAQ

Q: Can these be used outdoors without rusting?

A: Yes, 304 stainless steel offers excellent corrosion resistance for most outdoor environments. However, in highly corrosive environments like direct ocean spray, 316 grade might be preferred for long-term use.

Q: Is a VAT invoice included with the order?

A: Yes, as mentioned in the product description, a valid VAT invoice is automatically generated and included with your shipment or sent via email upon request.

Q: What size Allen key do I need for the M4 screws?

A: For M4 flat head hex socket screws, you typically need a 2.5mm Allen key (hex wrench).

Q: Are these screws magnetic?

A: 304 stainless steel is generally non-magnetic or very slightly magnetic depending on the manufacturing process. These specific black oxide coated screws show minimal magnetic attraction.

Q: Does the black coating wear off easily?

A: The black oxide finish is durable for standard applications. It may show wear over time if subjected to heavy abrasion or frequent tightening and loosening, but it provides good protection against surface rust.

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