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Home / Screws / Grade 8.8 Galvanized Socket Cap Screws Cylinder Head Screws Cup Head High-Strength Bolts 5 M6 M8 M10 M12 M14 M16

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Screws
Origin -
Material Grade Grade 8.8 High-Strength Steel
Surface Finish Galvanized Blue-White Zinc Plating
Head Style Socket Cap (Cylinder/Cup Head)
Drive Type Internal Hex (Allen)
Available Sizes M6, M8, M10, M12, M14, M16
Thread Type Metric Coarse Thread
Tensile Strength Minimum 800 MPa
Yield Strength Minimum 640 MPa
Corrosion Resistance Enhanced via Galvanization
Application Machinery, Automotive, and Structural Assembly

6 reviews

A

Anonymous

Mar 30, 2026

Rating: 5/5

Excellent corrosion resistance

Used these on an outdoor gate mechanism. After six months of rain and sun, there is no sign of rust thanks to the galvanization. Highly recommended for outdoor use.

A

Anonymous

Mar 24, 2026

Rating: 5/5

Perfect for heavy machinery repair

These bolts are exactly what I needed for my lathe repair. The galvanization looks solid and the hex heads fit my tools perfectly without stripping.

A

Anonymous

Mar 24, 2026

Rating: 5/5

Stock up item for our shop

We go through a lot of socket cap screws. These are reliable, consistent in sizing, and the price point allows us to keep a full inventory of M6 through M16.

A

Anonymous

Mar 15, 2026

Rating: 4/5

Good quality, fast shipping

Ordered the M10 size for a custom bracket project. They are strong and well-made. Took off one star because the packaging was a bit loose, but the bolts themselves are great.

A

Anonymous

Mar 07, 2026

Rating: 5/5

True Grade 8.8 specification

As a mechanical engineer, I verify my hardware. These meet the stated tensile strength requirements. The blue-white zinc coating is uniform and provides good protection.

A

Anonymous

Mar 01, 2026

Rating: 4/5

Strong but check your thread pitch

Very sturdy bolts. Just make sure you know you are buying coarse thread if that's what your project needs. I used them for a deck railing modification and they hold tight.

5 FAQ

Q: Do these come with matching washers included?

A: No, these are sold as standalone screws. We recommend purchasing compatible flat washers and lock washers separately for optimal installation.

Q: What is the exact length of the M8 option listed?

A: The listing includes various lengths for each diameter. Please select your specific required length (e.g., 20mm, 30mm, 50mm) from the dropdown menu before adding to cart.

Q: Are these suitable for high-temperature environments?

A: Grade 8.8 steel has good thermal properties, but the zinc galvanization may degrade at temperatures consistently above 200°C (392°F). For extreme heat, please consult an engineer.

Q: Can I use a standard metric Allen key for these?

A: Yes, these feature a standard internal hex drive compatible with standard metric Allen keys or hex bits corresponding to the screw diameter.

Q: Is the threading full length or partial?

A: For socket cap screws of this grade, the threading is typically full length for sizes up to M16, ensuring maximum grip in tapped holes.

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