Full spectrum of industrial fastening solutions | Covering both standard and custom parts
Our Stainless Steel Square Head Bolts are durable metric fasteners designed for machinery, equipment assembly, industrial maintenance, construction, and custom fastening applications. Compared with standard hex head bolts, square head bolts provide a larger gripping surface and are commonly used where better wrench engagement, anti-rotation performance, or traditional fastening style is required.
These bolts are made from stainless steel, commonly available in A2-70 / 304 stainless steel, offering good corrosion resistance, clean appearance, and reliable mechanical performance. The full threaded design provides strong engagement with matching nuts or threaded holes.
Available in common metric sizes including M4, M5, M6, M8, M10, and M12, these square head bolts are suitable for both standard and customized fastening requirements.
| Item | Description |
|---|---|
| Product Name | Stainless Steel Square Head Bolt |
| Material | Stainless Steel |
| Common Grade | A2-70 / 304 Stainless Steel |
| Head Type | Square Head |
| Thread Type | Metric Thread |
| Threading | Fully Threaded |
| Available Sizes | M4, M5, M6, M8, M10, M12 |
| Surface Finish | Plain Stainless Steel |
| Drive Type | External Square Head |
| Application | Machinery, equipment, construction, industrial fastening, repair |
Unit: mm
| Thread Size | Pitch | Head Thickness K | Square Head Width S |
|---|---|---|---|
| M4 | 0.7 | 2.7–3.24 | 6.64–7 |
| M5 | 0.8 | 3.26–3.74 | 7.64–8 |
| M6 | 1.0 | 3.76–4.24 | 9.64–10 |
| M8 | 1.25 | 4.76–5.24 | 12.57–13 |
| M10 | 1.5 | 5.76–6.24 | 15.57–17 |
| M12 | 1.75 | 6.71–7.29 | 17.57–19 |
Square head bolts are bolts with a four-sided head instead of a hexagonal head. The square head provides a large contact area for tools and can also help prevent rotation when installed in a matching square slot or channel.
They are commonly used in:
| Application | Function |
|---|---|
| Machinery Assembly | Secure fastening and positioning |
| Industrial Equipment | Durable connection in maintenance work |
| Construction Projects | Structural and bracket fastening |
| Wood and Metal Work | Traditional square head fastening |
| T-slot or Channel Systems | Helps reduce bolt rotation |
| Repair and Replacement | Suitable for non-standard or older equipment |
Stainless steel square head bolts are suitable for applications where corrosion resistance and clean appearance are important.
| Material Grade | Feature | Recommended Use |
|---|---|---|
| A2 / 304 Stainless Steel | Good corrosion resistance and general strength | Indoor, outdoor, machinery, equipment, furniture |
| A4 / 316 Stainless Steel | Better corrosion resistance in harsh environments | Marine, coastal, chemical, humid environments |
| Carbon Steel | Higher strength options, lower cost | Dry indoor use or coated fasteners |
For most general-purpose applications, A2-70 / 304 stainless steel square head bolts provide a good balance of corrosion resistance, durability, and cost performance.
| Industry | Typical Use |
|---|---|
| Machinery Manufacturing | Equipment assembly and fastening |
| Industrial Maintenance | Replacement bolts for machines and fixtures |
| Construction | Steel structure, brackets, supports |
| Furniture Production | Wood and metal furniture connections |
| Automotive Repair | Custom mounting and repair applications |
| Agricultural Equipment | General fastening and maintenance |
| DIY Projects | Home repair and custom fabrication |
| Marine & Outdoor Use | Stainless steel corrosion-resistant fastening |
These Stainless Steel Square Head Bolts are designed for secure and durable fastening. The square head makes the bolt easy to grip with tools and can help prevent spinning during installation in suitable applications.
The stainless steel material provides good resistance to rust and corrosion, making these bolts suitable for indoor, outdoor, and general industrial environments. With full metric threading, they can be used with matching metric nuts, washers, or threaded holes.
Before placing an order, please confirm the following details:
| Required Information | Example |
|---|---|
| Size | M4, M5, M6, M8, M10, M12 |
| Length | 10mm, 20mm, 30mm, 50mm, customized |
| Material | A2 / 304 stainless steel, A4 / 316 stainless steel |
| Thread Type | Full thread or partial thread |
| Quantity | Small pack or bulk order |
| Matching Accessories | Nuts, flat washers, spring washers |
Please use matching metric nuts and washers for correct assembly. If the bolt will be used in marine or chemical environments, 316 stainless steel is recommended.
| Matching Product | Function |
|---|---|
| Stainless Steel Square Nuts | Traditional matching fastening |
| Stainless Steel Hex Nuts | General fastening connection |
| Flat Washers | Load distribution and surface protection |
| Spring Washers | Anti-loosening support |
| Custom Fasteners | For special machinery or drawing-based production |
A square head bolt is a bolt with a four-sided square head. It provides strong tool grip and can help prevent rotation when used in square slots or special fixtures.
They are made from stainless steel. Common material options include A2-70 / 304 stainless steel and A4 / 316 stainless steel.
A2 usually refers to 304 stainless steel, and 70 refers to the strength class. A2-70 stainless steel fasteners are widely used for general corrosion-resistant applications.
Common sizes include M4, M5, M6, M8, M10, and M12. Other sizes can be customized according to drawings or samples.
Yes, the product shown is a fully threaded square head bolt. Partial thread versions can also be customized if required.
Yes. Stainless steel square head bolts can be used outdoors. For normal outdoor use, 304 stainless steel is suitable. For marine or highly corrosive environments, 316 stainless steel is recommended.
They can be installed with an adjustable wrench, open-end wrench, spanner, or custom fixture that fits the square head.
Yes. Matching stainless steel nuts, flat washers, spring washers, and custom fastener sets can be supplied.
Yes. Length, material, thread type, surface finish, and packaging can be customized according to customer requirements.
They are commonly used in machinery, construction, industrial equipment, furniture assembly, agricultural machinery, repair work, and custom fastening projects.
Stainless Steel Square Head Bolts M4 M5 M6 M8 M10 M12 are corrosion-resistant metric fasteners with a four-sided square head and fully threaded body. Made from stainless steel, commonly A2-70 / 304 stainless steel, they are suitable for machinery, construction, industrial equipment, furniture, repair work, and custom fastening applications. Matching nuts, washers, customized sizes, and bulk packaging are available.
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Complies with major global standards such as ISO/DIN/GB/ANSI/JIS
Standard parts + customized parts, one-stop solution for all your fastening needs
Tolerance control far exceeds industry standards, ranging from 4.8 to 12.9 grades.
Customization based on provided drawings/samples/working conditions; rapid prototyping and mass production delivery.
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International Organization for Standardization (ISO) standards
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