M6 x 50mm Hexagon Head Set Screws – A4-70 Marine Grade Stainless Steel DIN 933

Our M6 x 50mm A4-70 stainless steel hexagon head set screws are manufactured from high-quality A4 (316) marine grade stainless steel, providing excellent corrosion resistance and reliable mechanical strength for demanding environments.

Manufactured to DIN 933, these fully threaded hexagon head bolts feature a metric M6 thread extending along the shank towards the underside of the head, making them ideal for securely fastening components of varying thicknesses.

Also commonly known as M6 x 50mm marine grade stainless steel hex bolts, A4-70 setscrews or fully threaded hexagon bolts, these fasteners are particularly suitable for applications exposed to moisture, saltwater, coastal conditions and corrosive environments.

Product Specifications

• Diameter: M6 (6mm)
• Length: 50mm (measured from underneath the head)
• Thread Pitch: 1.0mm metric coarse
• Head Type: External hexagon head
• Thread Type: Fully threaded
• Material: A4 (316) marine grade stainless steel
• Property Class: A4-70
• Standard: DIN 933 / ISO 4017
• Spanner Size (Across Flats): 10mm
• Minimum Tensile Strength: 700 N/mm² (700 MPa)
• Finish: Natural stainless steel

Key Features and Benefits

Marine Grade A4 (316) Stainless Steel: Contains molybdenum, providing improved resistance to chloride-induced corrosion compared with standard A2 (304) stainless steel.

Excellent Corrosion Resistance: Particularly suitable for coastal, marine and outdoor environments where moisture, humidity and salt exposure can cause conventional steel fasteners to deteriorate.

Fully Threaded Design: The metric M6 thread allows secure fastening with compatible stainless steel nuts, washers and internally threaded components.

Hexagon Head: Designed for installation using a standard 10mm spanner or socket, allowing secure tightening and straightforward maintenance.

A4-70 Strength Classification: Provides a minimum tensile strength of 700 MPa, combining mechanical strength with excellent resistance to corrosion.

Typical Applications

M6 x 50mm A4-70 stainless steel hexagon bolts are suitable for a wide range of demanding applications, including:

• Marine engineering and boat fittings
• Coastal construction and exposed structures
• Decking, balustrades and outdoor installations
• Stainless steel fabrication and assembly
• Water treatment equipment and installations
• Food processing and washdown environments
• Chemical processing equipment, subject to chemical compatibility
• General engineering and machinery exposed to moisture

Why Choose A4 Stainless Steel Instead of A2?

A4 (316) marine grade stainless steel offers enhanced resistance to chloride-related corrosion compared with A2 (304) stainless steel.

This makes A4-70 stainless steel hexagon bolts a preferred choice for marine, coastal and other demanding outdoor applications where long-term corrosion resistance is important.

Although A4 provides increased corrosion resistance, it is not completely immune to corrosion. Suitability depends on exposure conditions, installation and maintenance.

Why Buy from Swiftfix?

At Swiftfix, we specialise in supplying stainless steel bolts, nuts, washers and industrial fasteners to trade, engineering, construction and marine customers throughout the UK.

Our comprehensive range includes A2 (304) and A4 (316) stainless steel fasteners in a wide selection of diameters and lengths, allowing you to source the correct fixings for your project.

Whether you require marine grade stainless steel fasteners for boat maintenance, coastal construction, metal fabrication or general engineering, Swiftfix offers a convenient source for your fastening requirements.

Order your M6 x 50mm A4-70 marine grade stainless steel hexagon head set screws online from Swiftfix, with UK-wide delivery available.