M6 x 25mm Hexagon Flange Head Bolt A2 (304) Stainless DIN 6921

An M6 A2 Stainless Steel Hexagon Flange Head Bolt is a metric fastener designed to secure components together using a compatible nut or threaded hole. Its six-sided head provides a positive external drive for tightening with a spanner or socket, and the integral flange bears directly on the surface being clamped.

The bolt is manufactured from A2 (304) stainless steel, offering corrosion resistance for many general-purpose applications. Its DIN 6921 specification identifies a hexagon flange head bolt with a metric coarse thread.

• Nominal diameter: M6 (6mm).
• Overall length: 25mm, measured from beneath the flange to the tip.
• Head type: Hexagon flange head.
• Thread: Metric coarse, 1.0mm pitch.
• Material: A2 (304) stainless steel.
• Standard: DIN 6921.

M6 A2 stainless steel hexagon flange head bolts are suitable for many general fastening applications where a metric bolt and compatible nut or tapped hole are required. The integral flange can be useful where a larger bearing surface is needed under the head, or where a separate washer would otherwise be fitted.

Typical applications may include:

• Securing brackets, plates and metal components.
• General engineering, maintenance and assembly work.
• Fixing machinery components and equipment.
• Fabrication projects using compatible metric fasteners.
• Applications where stainless steel corrosion resistance is beneficial.

Choose the bolt length, thread engagement and mating fastener to suit the joint. Consider the applied load, material compatibility, operating environment and any relevant engineering requirements before installation.

This bolt is specified to DIN 6921, covering metric hexagon bolts with a flange. The following dimensions are standard-based nominal values for the M6 × 25mm size.

• Standard: DIN 6921.
• Material: A2 (304) stainless steel.
• Nominal thread diameter: 6mm.
• Metric coarse thread pitch: 1.0mm.
• Spanner size: 10mm across flats.
• Nominal head height: 5.4mm.
• Nominal flange diameter: 14.2mm.
• Nominal thread length: 18mm.
• Nominal overall length: 25mm, measured from beneath the flange.

A2 stainless steel provides corrosion resistance in many general-purpose environments but is not suitable for every chemical, marine or highly corrosive application. Check the manufacturer's documentation where a specific mechanical property, approval or operating condition is required.

What does M6 mean?
M6 identifies a metric thread with a nominal diameter of 6mm. The standard coarse thread pitch for M6 is 1.0mm.

What does DIN 6921 mean?
DIN 6921 is the dimensional standard for metric hexagon bolts with an integral flange under the head.

What spanner size is required?
The standard nominal spanner size for an M6 DIN 6921 hexagon flange head bolt is 10mm across flats.

What is the difference between a flange head bolt and a standard hexagon head bolt?
A flange head bolt has a wider integral flange under the head, which increases the bearing area against the clamped surface. A standard hexagon head bolt has no flange and is often used with a separate washer.

What are the benefits of A2 stainless steel?
A2 stainless steel, commonly associated with grade 304, offers corrosion resistance for many general-purpose environments. It is not suitable for every highly corrosive environment.

Can this bolt be used outdoors?
It may be suitable for many outdoor applications, depending on exposure and environmental conditions. Consider the risk of corrosion and the compatibility of the other materials in the assembly.

What nut should be used with this bolt?
Use a compatible M6 metric nut with a matching thread and suitable material and strength properties for the application.

How is the bolt length measured?
For a hexagon flange head bolt, the nominal length is measured from the underside of the flange to the end of the bolt, excluding the head height.