Schletter Screw M8x20 Hexagon Socket, ISO 4762, A2-70 DL | 943000-025

Description

This Schletter M8 x 20mm hexagon socket screw is manufactured to ISO 4762 with an under-head serration that locks the screw in place once tightened, resisting loosening under vibration.

Its hexagon socket (Allen-key) drive gives strong, reliable torque transfer, particularly useful in confined spaces where a standard spanner or Torx driver may not have clearance.

M8 x 20mm

Screw Size

ISO 4762

Standard

A2-70

Material Grade

Hex Socket

Drive Type

Serrated Underhead

Locking Feature

Stainless Steel

Material Class

Key Features

Locking Serration Under the Head

The serrated underside of the head bites into the mating surface as the screw is tightened, resisting loosening under vibration without a separate lock washer.

ISO 4762 Manufacturing Standard

Produced to the recognised ISO 4762 hexagon socket head cap screw specification, giving a documented basis for structural sign-off.

A2-70 Stainless Steel Grade

Manufactured in A2-70 stainless steel, offering a strength class suited to structural fastening while retaining good corrosion resistance.

Hexagon Socket Drive

The hexagon socket (Allen-key) drive gives strong torque transfer, useful in tight fixing locations where other drive types may lack clearance.

Technical Specification

Screw Specification

Thread Size

M8

Length

20 mm

Manufacturing Standard

ISO 4762

Drive Type

Hexagon socket

Locking Feature

Serrated under-head

Materials

Material Grade

A2-70 stainless steel

Frequently Asked Questions

What does the under-head serration do?

It bites into the mating surface as the screw is tightened, providing resistance to loosening from vibration without needing a separate lock washer.

What tool do I need to fit this screw?

A hexagon socket (Allen key) driver or bit matching the screw's socket size.

What grade of stainless steel is this screw made from?

A2-70, giving a strength class suited to structural fastening while retaining good general corrosion resistance.

What standard is this screw manufactured to?

ISO 4762, the recognised specification for hexagon socket head cap screws.

Where is this screw typically used within Schletter systems?

It's used as a general-purpose M8 fastening screw across various Schletter mounting connections; confirm the specific application against your system's documentation.

BTU Calculator

BTU & WATT Calculator

Room Dimensions

Length (in m):

Width (in m):

Height (in m):

Room Type

Living Room

Bedroom

Kitchen

Bathroom

Conservatory

Hallway

Glazing Type

Single Glazed

Double Glazed

Triple Glazed

External Walls

0 Wall

1 Wall

2 Walls

3 Walls

4 Walls

Insulation Level

Poor

Average

Good (New Build)

Calculate

Required Heating

0

Watts

0

BTUs