Attributes

Brand	-
Category	Standard Parts, Components & Industrial Consumables / Screws
Origin	-
Material Grade	Alloy Steel 12.9
Head Style	Socket Head Cap (Cylindrical)
Drive Type	Internal Hex (Allen)
Thread Standard	Metric Coarse (ISO)
Available Sizes	M3, M4, M5, M6, M8
Length Options	10mm, 20mm, 30mm, 45mm
Surface Finish	Black Oxide Coated
Tensile Strength	1220 MPa (Minimum)
Hardness	39-44 HRC
Application	Machinery, Automotive, Robotics

6 reviews

Anonymous

Mar 28, 2026

Rating: 4/5

Good strength, packaging could be better

The bolts themselves are top-notch and very strong. Only minor complaint is that they arrived loose in a bag rather than sorted by size, but no damage occurred.

Anonymous

Mar 19, 2026

Rating: 5/5

True to specification

As an engineer, I verified the hardness and dimensions. These meet the ISO standards for Grade 12.9 perfectly. Highly recommended for critical applications.

Anonymous

Mar 14, 2026

Rating: 5/5

Excellent quality for precision machinery

These screws are exactly what I needed for my CNC router assembly. The 12.9 grade is genuinely hard, and the hex sockets are perfectly formed without any stripping issues.

Anonymous

Mar 12, 2026

Rating: 4/5

Great product, fast shipping

Needed M3 screws for a small electronics project. They are slightly overkill for plastic, but the quality is undeniable. Arrived two days early.

Anonymous

Mar 11, 2026

Rating: 5/5

Reliable for automotive use

Using these on a custom suspension bracket. The high tensile strength gives me peace of mind under load. Will definitely order again.

Anonymous

Mar 04, 2026

Rating: 5/5

Perfect fit and finish

Ordered the M5x20mm size. Threads are clean, black oxide coating is even, and they tightened down smoothly. Great value for high-strength fasteners.

5 FAQ

Q: Do you sell these in bulk packs of 100?

A: Yes, we offer bulk packaging options for all sizes. Please select the 'Bulk Pack' option on the product page or contact us for custom quantities.

Q: Are these screws suitable for outdoor use?

A: While the black oxide provides some corrosion resistance, for prolonged outdoor exposure we recommend applying an additional sealant or choosing stainless steel variants if available.

Q: Is the thread full length or partial?

A: These socket head cap screws feature full threading along the entire shank length for maximum grip in tapped holes.

Q: What size Allen key do I need for the M6 bolt?

A: For standard metric M6 socket head cap screws, you will typically need a 5mm Allen key (hex wrench).

Q: Can these be used with aluminum parts?

A: Yes, but please ensure you use appropriate washers to prevent galvanic corrosion between the steel screw and aluminum component.

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