Countersunk bolts (also known as flathead bolts) are designed with a conical head that sits flush within a countersunk hole, creating a smooth surface finish. This makes them ideal for applications where aesthetics, aerodynamics, or space constraints are critical, such as furniture, automotive components, electronics, and architectural fixtures. Their secure threading and flush design ensure both functionality and visual appeal.
| Attribute |
Details |
| Type |
- Standard Countersunk Bolts
- High-Strength Countersunk Bolts
- Stainless Steel Countersunk Bolts |
| Material |
- Carbon Steel: Grade 4.8, 8.8 (zinc-plated)
- Stainless Steel: 304/316 (A2/A4, corrosion-resistant)
- Alloy Steel: Grade 10.9 (heat-treated for high-tension applications) |
| Finish |
- Zinc Plating (Yellow/Clear, RoHS/REACH compliant)
- Passivated (Stainless Steel)
- Black Oxide, Dacromet (for heavy-duty corrosion resistance) |
| Head Design |
- Countersink Angle: Standard 82° or 90° (ISO 1003, ASME B18.3)
- Head Diameter: 6–30 mm (0.24"–1.18")
- Flush Mount: Ensures no protrusion above the surface |
| Thread Type |
- Metric (M3–M24, ISO 965-1)
- Imperial (1/4"–1", UNC/UNF)
- Fine Threads (for precision applications) |
| Length Range |
5 mm (0.2") – 100 mm (4") (standard); custom lengths up to 200 mm (8") available |
| Standards Compliance |
- ISO 7045 (Metric Countersunk Bolts)
- ASME B18.3 (Inch Countersunk Screws/Bolts)
- DIN 963 (German Standard for Countersunk Bolts) |
| Applications |
- Furniture: Tables, chairs, and cabinets (flush joinery).
- Automotive: Interior trim, body panels, and under-hood components.
- Electronics: Enclosures, control panels, and machinery covers.
- Aerospace: Lightweight components requiring smooth surfaces. |
| Corrosion Resistance |
- Salt Spray Test: 500+ hours (zinc-plated); 1,000+ hours (stainless steel) |
| Packaging |
- Bulk: 25 kg cartons with anti-rust paper
- Retail: Blister packs (100/500 pieces)
- Custom: Anti-static bags for electronics industry |
| Certifications |
- RoHS, REACH, CE
- ISO 9001:2015
- Material Test Certificates (MTC) |
| Minimum Order Quantity (MOQ) |
1,000 Pieces (standard sizes); 2,000 Pieces (stainless steel/custom finishes) |
| Delivery Time |
10–20 Days (standard); 25–35 Days (custom head angles/sizes) |
| Customization |
- Non-Standard Countersink Angles (e.g., 100°, 110°)
- Special Coatings (PTFE, color-matched)
- Laser Engraved Part Numbers or Logos |
-
Flush-Mount Aesthetics
- The conical head sits perfectly within countersunk holes, providing a seamless surface for furniture, automotive trim, and architectural designs.
-
Space-Saving Design
- Reduces protrusion in tight spaces, making them suitable for components that require low profiles (e.g., sliding doors, machinery covers).
-
Corrosion Resistance
- Marine-grade 316 stainless steel and Dacromet-coated options ensure durability in harsh environments (coastal, industrial, or outdoor use).
-
Precision Engineering
- Tight tolerances on head angles and thread pitches ensure compatibility with standard countersink drills and tools.
-
Global Compatibility
- Meets ISO, ASME, and DIN standards, facilitating use in international projects and OEM manufacturing.
- Incorrect Hole Angle: Always match the countersink angle (82° or 90°) to the bolt head to ensure full seating and load distribution.
- Over-Tightening: Use torque wrenches to avoid stripping threads, especially in soft materials like aluminum or plastic.
- Wrong Material for Load: Do not use low-grade carbon steel for heavy-duty applications; upgrade to alloy steel or stainless steel for high-tension needs.
-
Versatile Material Options: From cost-effective zinc-plated carbon steel to high-strength stainless steel, suitable for all industries.
-
Custom Solutions: Tailored head sizes, angles, and coatings to meet unique project requirements.
-
Efficient Logistics: Bulk orders shipped via FCL/LCL with competitive freight rates, and fast delivery on stocked sizes.
Contact Us for Custom Quotes!
Need technical drawings, torque specifications, or samples? Our team can assist with selecting the right countersunk bolts for your application.
JH Bolt Co., Ltd is a professional manufacturer of different types of bolts with more than 15 years rich manufacturer experience. The factory area is more than 1500 squares with more than hundreds different types ofnevproduction machines. There are more than 50 people who work here for at least 5 years.With quality &customer frst, staffs second, then company, Our products are widely recog-nized and trusted by users all over the world. Proft for the development of communication, We are here for you 12 hours a day, 7 days a week!
