DIN 603, bomb-headed and square-neck bolts Definitions. These bolts are used especially in wood connections, park furniture, fence systems, prefabricated structures, and decorative installations. The head is semi-spherical (domed) in shape, providing an aesthetic appearance, while the square neck provides resistance to rotation during connection. When the nut is tightened, the square neck embeds itself into the assembled part, securing it in place. DIN 603 bolts are generally DIN 934 nut and DIN 125 Used with a flat washer. It is a product particularly preferred in wood flooring applications. ISO 8677 It is largely compliant with the standard; minor tolerance differences may exist in some measurements.
| Feature | |
| Standard | DIN 603 |
| Material | Carbon Steel, Stainless Steel |
| Type | Bomb Head Square Neck Bolt |
| Quality | 4.6, 5.6, 8.8, A2, A4 |
| Coating | Electrogalvanized (White/Yellow), Hot-Dip Galvanized (HDG), Black Oxide |
| Tooth Type | Metric (Coarse) |
| Measurement Range | From M5 to M42, 1/2″-1 5/8″ |
| Production Method | Cold forging, hot forging |
| Thread Direction | Right-Hand Thread (standard) / Left-Hand Thread (upon request) |
- Wooden structures
- Park and garden furniture
- Play areas and safety panels
- Lightweight metal-wood composite systems
- Interior and exterior decorative fittings
- ISO 9001:2015 Quality Management System
- ISO 14001:2015 Environmental Management System
- ISO 45001:2018 Occupational Health and Safety Management System
- EU Declaration of Conformity (PED) certificate (Compliance with the Pressure Equipment Directive)
- Our production processes, DIN, EN, ISO, and ASTM is fully compliant with the standards
- Upon request EN 10204 3.1 certificate is provided
The square neck fits into the hole during installation and prevents rotation. This provides significant convenience, especially in single-sided installations.
It offers an aesthetic appearance and is preferred for safety reasons as it has no sharp edges. It is frequently used in places such as children's playgrounds and parks.
Yes. A2 (304) stainless steel offers medium corrosion resistance. A4 (316) grade should be preferred in coastal areas and chemical environments.