M8 12.9 Zinc Socket Cap Bolts DIN 912

Product Description

M8 Class 12.9 Zinc-Plated Socket Cap Bolts

These M8 socket head cap bolts are manufactured from high-tensile class 12.9 steel and protected with a zinc-plated finish. Their cylindrical cap head and internal hexagon drive provide strong, compact fastening for machinery, equipment, automotive and general engineering applications.

Each bolt has a standard M8 × 1.25mm metric coarse thread and a partially threaded shank. The unthreaded section provides a solid bearing surface through the joined components, making these bolts suitable for applications involving alignment, shear loading or clamping through thicker assemblies.

Product Details

• Thread size: M8
• Thread pitch: 1.25mm metric coarse
• Available lengths: 40mm, 45mm, 50mm, 55mm, 60mm, 70mm, 75mm, 80mm, 90mm, 100mm, 120mm, 130mm and 150mm
• Material: High-tensile steel
• Property class: 12.9
• Finish: Zinc plated
• Head style: Cylindrical socket cap head
• Nominal head diameter: 13mm
• Nominal head height: 8mm
• Drive type: Internal hexagon
• Required hex key: 6mm
• Thread coverage: Partially threaded with an unthreaded shank
• Current standard: BS EN ISO 4762:2004 / ISO 4762
• Legacy standard: DIN 912
• Mechanical-property standard: BS EN ISO 898-1

Corrected Length and Thread Details

The selected bolt length is measured from beneath the cylindrical head to the end of the bolt. The head is not included in the stated length.

Thread lengths are standard reference dimensions for partially threaded ISO 4762 fasteners. Manufacturing tolerances apply, and the thread may extend slightly further along the shank.

Class 12.9 High-Tensile Steel

Property class 12.9 is designed for highly loaded engineering fasteners requiring high tensile and proof strength. The mating nut or tapped component, available thread engagement and tightening method must all be suitable for a class 12.9 fastener.

The zinc-plated finish provides additional corrosion protection compared with an untreated self-colour surface. It is intended for general engineering conditions and should not be treated as a substitute for stainless steel or a specialist coating in aggressive, marine or continuously wet environments.

Typical Applications

• Machinery and equipment assembly
• Automotive and motorsport components
• Jigs, fixtures and tooling
• Production and automation equipment
• Engineering brackets and frames
• Applications requiring a long unthreaded shank
• High-strength mechanical assemblies

Installation Guidance

Install using a correctly fitting 6mm hex key or socket bit. Ensure the mating thread is clean, correctly formed and provides sufficient thread engagement for the application.

Tightening torque depends on the joint design, coating, lubrication, mating materials and operating conditions. Use the torque specified by the equipment manufacturer or a suitably qualified engineer rather than applying a generic value.

Pack Quantities

Available individually or in packs of 5, 10, 20, 50, 100, 250, 500 or 1,000 bolts, depending on the selected length.

View our complete range of metric socket cap screws.