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

Request A Quote

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

DIN7991 Countersunk Socket Head Bolt Grade 8.8 10.9 12.9 Stainless Steel Flat Head Allen Screw.png

How To Install DIN7991 Countersunk Screws For Flush Surface

2026-07-23

1. IntroductionDIN7991 countersunk socket screws feature a 90° conical head, which can sink fully into the workpiece to achieve flush surface assembly. They are widely adopted in automation machinery, precision molds, instrument housings, aluminum profiles and mobile tooling where protruding fastene

2026-07-23

How To Match DIN6334 Long Hex Nut With Threaded Rod

2026-07-22

1. IntroductionDIN6334 long hex nuts are specialized extended fasteners different from standard short DIN934 nuts. With extended thread engagement length, they are widely used for threaded rod adjustment, pipe hangers, solar bracket positioning, fixture assembly and machinery leveling structures tha

2026-07-22

Mechanical Difference Between DIN6921 And Ordinary DIN933 Bolts

2026-07-21

1. IntroductionDIN6921 flange bolts and DIN933 standard hex bolts are the two most commonly used metric fasteners in mechanical assembly, automotive manufacturing, solar brackets and automation equipment. Due to similar thread specifications and overlapping dimensions, many buyers and engineers repl

2026-07-21

Get A Free Quate

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

How To Install DIN7991 Countersunk Screws For Flush Surface

How To Match DIN6334 Long Hex Nut With Threaded Rod

Mechanical Difference Between DIN6921 And Ordinary DIN933 Bolts

Get A Free Quate

Quick Links

Fasteners

Contact Us

Join Our Newsletter