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Home / Connectors and Fasteners / Weinai Grade 8.8 High-Strength Cup Head Socket Cap Bolts, Cylinder Head Screws, Studs M4 M5 M6 M8 M10-M20

Attributes

Brand -
Category Industrial Small Parts / Connectors and Fasteners
Origin -
Material Carbon Steel
Strength Class 8.8
Head Type Cylinder Head
Drive Style Internal Hex
Thread Standard Metric Coarse
Surface Finish Black Oxide
Compliance Standard DIN 912
Available Sizes M4 to M20
Package Contents Assorted Kit
Country of Origin China

5 reviews

A

Anonymous

Apr 04, 2026

Rating: 5/5

Quick Shipping

Packaged securely in a sturdy box. No rust or damage upon arrival.

A

Anonymous

Feb 17, 2026

Rating: 5/5

Solid Construction

Great for general mechanical assembly. The heads did not strip under torque.

A

Anonymous

Feb 15, 2026

Rating: 5/5

Reliable Fasteners

No stripping during installation. Used them on a high vibration motor mount.

A

Anonymous

Jan 31, 2026

Rating: 5/5

True to Size

Dimensions match the spec sheet perfectly. Very satisfied with the precision.

A

Anonymous

Jan 29, 2026

Rating: 4/5

Good Value

Quality is good for the price point. Shipping was slightly delayed but product is fine.

5 FAQ

Q: Do you sell matching nuts?

A: Yes, please check our related products section for compatible hex nuts.

Q: Is this suitable for outdoor use?

A: Black oxide offers mild resistance. We recommend additional coating for harsh environments.

Q: What key size for M8?

A: A 6mm hex key is required for M8 socket head cap screws.

Q: Can I return opened packages?

A: Please review our return policy details on the checkout page for specifics.

Q: What is the hardness rating?

A: Typically 22-32 HRC for Grade 8.8 carbon steel fasteners.

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