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: Flat Surface Connection & Anti-Rotation Advantage

2026-09-02

1. IntroductionDIN557 square nut is a specialized four-sided standard fastener widely used in European industrial and construction fields. Different from conventional hexagonal nuts, its unique square structure delivers natural anti-rotation performance and larger flat bearing area, solving common a

2026-09-02

din_913_black_oxide_coating_hex_socket_set_screw_with_flat_point.jpg

DIN913 Socket Set Screw Flat Point: Positioning Assembly & Torque Tips

2026-09-01

This article focuses on the structural characteristics and core advantages of DIN913 flat point socket set screws, distinguishes the application differences from cone-point and cup-point set screws, sorts out standard assembly torque control and correct operation specifications, summarizes common installation failure causes and solutions, and provides professional selection and construction guidance for precision machinery, automation tooling and equipment positioning assembly.

2026-09-01

DIN1587 Cap Nut: Dome Nut Material Selection And Surface Finish Options

2026-08-31

This article introduces the structural advantages and dual protection & decoration functions of DIN1587 dome cap nuts, analyzes the applicable scenarios of carbon steel and stainless steel materials, compares the characteristics and environmental adaptation standards of various surface treatments, summarizes installation specifications and common mistakes, and provides professional material and process selection guidance for architectural decoration, mechanical assembly and outdoor engineering projects.

2026-08-31

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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: Flat Surface Connection & Anti-Rotation Advantage

DIN913 Socket Set Screw Flat Point: Positioning Assembly & Torque Tips

DIN1587 Cap Nut: Dome Nut Material Selection And Surface Finish Options

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