ASME/ANSI B18.9:2007 Countersunk Square Neck Bolt is suitable for inch-series joints that require a flush surface and anti-rotation support. The countersunk head reduces exposed height, while the square neck provides mechanical locking during installation.
This bolt is commonly used in wood structures, vehicle panels, steps, rail accessories, and assemblies requiring one-side fastening. The countersunk appearance is neat and less likely to snag, making it useful for areas requiring surface flatness and contact safety.
Countersink form, square-neck size, thread series, and grip length should be confirmed. For outdoor, vehicle, or humid environments, higher-grade coatings or corrosion-protection treatments can help maintain long-term stability.

Unit: inch
|
Nominal diameter d |
dk(max) |
dk(min) |
k(max) |
k(min) |
s(max) |
s(min) |
ds(max) |
ds(min) |
|
Thicken |
||||||||
|
5/16 |
0.605 |
0.563 |
0.269 |
0.243 |
0.325 |
0.313 |
0.312 |
0.299 |
|
3/8 |
0.708 |
0.656 |
0.312 |
0.281 |
0.387 |
0.375 |
0.375 |
0.36 |
|
7/16 |
0.826 |
0.766 |
0.364 |
0.328 |
0.45 |
0.438 |
0.438 |
0.421 |
|
1/2 |
0.945 |
0.875 |
0.417 |
0.375 |
0.515 |
0.5 |
0.5 |
0.483 |
|
9/16 |
1.045 |
0.969 |
0.461 |
0.416 |
0.578 |
0.563 |
0.592 |
0.544 |
|
5/8 |
1.147 |
1.063 |
0.506 |
0.456 |
0.64 |
0.625 |
0.657 |
0.606 |
|
3/4 |
1.303 |
1.219 |
0.541 |
0.491 |
0.765 |
0.75 |
0.782 |
0.729 |
|
7/8 |
1.512 |
1.406 |
0.626 |
0.563 |
0.906 |
0.875 |
0.938 |
0.853 |
|
1 |
1.7 |
1.594 |
0.69 |
0.627 |
1.031 |
1 |
1.062 |
0.976 |
|
Standard |
||||||||
|
5/16 |
0.556 |
0.516 |
0.232 |
0.212 |
0.325 |
0.313 |
0.312 |
0.299 |
|
3/8 |
0.659 |
0.609 |
0.272 |
0.247 |
0.387 |
0.375 |
0.375 |
0.36 |
|
7/16 |
0.779 |
0.719 |
0.324 |
0.294 |
0.45 |
0.438 |
0.438 |
0.421 |
|
1/2 |
0.898 |
0.828 |
0.375 |
0.34 |
0.515 |
0.5 |
0.5 |
0.483 |
|
9/16 |
1.002 |
0.922 |
0.423 |
0.383 |
0.578 |
0.563 |
0.592 |
0.544 |
|
5/8 |
1.096 |
1.016 |
0.458 |
0.418 |
0.64 |
0.625 |
0.657 |
0.606 |
|
3/4 |
1.252 |
1.172 |
0.493 |
0.453 |
0.765 |
0.75 |
0.782 |
0.729 |
|
7/8 |
1.465 |
1.359 |
0.573 |
0.523 |
0.906 |
0.875 |
0.938 |
0.853 |
|
1 |
1.653 |
1.547 |
0.637 |
0.587 |
1.031 |
1 |
1.062 |
0.976 |
FAQ
A: We take every inquiry seriously. On working days, we will respond within 12 hours after receiving your inquiry.
A: We focus on the production of fasteners made of carbon steel, stainless steel, and low-alloy steel. We are a direct manufacturer with independent production capacity. ASME/ANSI B18.9:2007 Countersunk Square Neck Bolt Factory. We own several fastener manufacturing facilities and have an international sales department, providing full-process services from production to export.
A: Customized production is our core business. We can develop and manufacture products based on the drawings or samples you provide.
A: Yes. In addition to custom products, we also produce general construction machinery parts (GET parts) for equipment such as excavators, including bucket teeth, tooth holders, corner blades, pins, clips, bolts and nuts. ASME/ANSI B18.9:2007 Countersunk Square Neck Bolt Wholesale.
A: We have 12 energy-efficient and environmentally friendly modern production lines (including one fully automatic shell molding line and four heat treatment lines), with an annual production capacity exceeding 20,000 tons, enabling us to steadily meet various order requirements.
A: Trade terms (such as FOB, CIF, etc.) are confirmed when quoting. For batch production, we typically require a 30% deposit, with the balance paid against the copy of the bill of lading. T/T is the main payment method accepted, and L/C can also be negotiated.
A: We are only 35 km away from Shanghai Port and Ningbo Port, so sea freight is the main mode of transportation, which is convenient and efficient. For urgent deliveries, we can also arrange air freight via Ningbo or Shanghai airports.
About Us
Better Fastener is a professional fastener enterprise specializing in the manufacturing of steel washers, stainless steel washers, spring washers and sealingwashers. Founded in 2001 as a washer factory, the company expanded into a comprehensive enterprise integrating washers, nuts, bolts, spring nuts and other fastener products in 2010. ASME/ANSI B18.9:2007 Countersunk Square Neck Bolt Suppliers in China.
The company positions itself as a provider of comprehensive one-stop services for customers, relying on technological R&D, industrial investment and trade distribution.
With an experienced professional team and a sound sales network, Better Fastener has achieved excellent sales performance in both domestic and foreign markets,and has grown into one of the competitive manufacturers and suppliers in China's industrial fastener industry.
Better Fastener is committed to becoming a trusted fastener supplier for customers with reliable product quality, reasonable prices and on-time deliveryNEWS