HEX BOLTS

The products are strictly conform with DIN, ISO, ASTM, ANSI, BS, JIS...

● Level: A325/A325M/A490/A490M/8.8 /10.9/12.9/Gr5/Gr8

● Coating: Plain/Black/Galvanized/H.D.G /YZP/Dacromet/Xylan

ASTM B7/B7M

THREAD RODS

The longest can reach 3.66 meters(12FT)

China Professional Metal Fasteners

Manufacturer and Supplier with Over 20 Years of Experience

Bolt

Head shape: Hexagonal head, square head, round head can all be produced.
Size: M4-M100, 3/8 "-4"...

Nut

Type: hex nut, cap nut, couple nut, lock nut, spring nut
Size: M4-M100, 3/8'-4' is divided...

Washer

Type: Flat washer, spring washer
Specifications: M3-M100, 1/4

Threaded Rod

Size: M4-M100, 3/8 "-4", divided into metric size and inch size
Thread type: Full Thread

Precast Accessories

Size: Customization based on drawings or samples, both metric size and inch size are available

Custom Fasteners

Size: Customization based on drawings or samples, both metric size and inch size are available

About Material

Carbon steel, alloy steel, stainless steel are all acceptable.
According to customer requirements

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Topbolt - Best Standard Bolts and Nuts for Your Industries

The products are applied to architectural steel structures, brigdes, oil, pipeline, machinery equipment, furniture, vessel, railway.

Bridge
Industry
Ship
Solar Power
Steel Structural

Why Choose Topbolt for Your Projects?

Trusted Supplier of Bolts, Nuts, and Fasteners Conforming to DIN, ANSI/IFI, JIS, BS, ISO, and GB Specifications.

Ningbo Topbolt Metalworks Co., Ltd. is a manufacturer in China which mainly produces high strength fasteners and specializes in all kinds of hardwares. Founded in 2001, In the past few years, it developed fast with its factory located in Ningbo Zhenhai Chemical industrial area and its headquarter /foreign sales department in Ningbo Jiangdong Eastern Business Centre.

The factory now covers an area of approximately 15,000 square meters, with monthly production capacity of 2000 tons. The company has its all-around research system, supply management, large-scale warehouse...

Founded In

㎡

Covers an Area

Monthly Production Capacity

million

Annual Sales

DIGITAL SHOWROOM

If you want to learn more about our manufacturing capabilities, you can click on the avatar in the scene, or accept my invitation!

What Makes Topbolt Fasteners Manufacturing Stand Out?

Material Science

Carbon steel, alloy steel, stainless steel, Special material customization
Direct procurement from raw material factories, discounted prices, and sufficient stock availability

Standard

Strictly produce according to standard dimensions such as DIN, ISO, GB, JIS, ASTM, SAE, ASME, etc

Services

Accept customized production (including sample processing, drawing processing), OEM production

Topbolt News & Fasteners Knowledge Center

DIN557 Square Nut: Feature And Matching Fastener Solutions

2026-08-24

1. IntroductionDIN557 square nut is a standard metric four-sided fastener widely adopted in European industrial and construction fields. Different from conventional hexagonal nuts, its unique square structural design delivers outstanding anti-rotation performance, larger contact bearing area and exc

2026-08-24

When To Choose B7 Eye Bolt Instead Of General 4140 Alloy Eye Bolt

2026-08-21

1. IntroductionB7 and 4140 eye bolts are both high-strength alloy steel lifting fasteners widely used for equipment hoisting, machinery anchoring, and structural lifting points. Many buyers mistakenly regard them as identical products because they share the same AISI 4140 base material. However, B7

2026-08-21

EN 14399‑1 Preload Structural Bolt: HR & HV Grade Assembly Difference

2026-08-20

1. IntroductionEN 14399-1 is the core European standard for high-strength preloaded structural bolt assemblies, widely adopted in European steel structure engineering, bridge construction, industrial plant frame installation, and heavy-duty mechanical connection projects. Unlike ordinary commercial

2026-08-20

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We welcome all of you from all over the world to join us for the win-win business partnership and friendship, welcome to China, welcome to Ningbo Topbolt!

China Professional Metal Fasteners

Topbolt - Best Standard Bolts and Nuts for Your Industries

Why Choose Topbolt for Your Projects?

DIGITAL SHOWROOM

DIN557 Square Nut: Feature And Matching Fastener Solutions

When To Choose B7 Eye Bolt Instead Of General 4140 Alloy Eye Bolt

EN 14399‑1 Preload Structural Bolt: HR & HV Grade Assembly Difference

Get A Free Quate

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