Britool England MDB 3/8" Deep AF 12 Point Socket Range 1/4"-7/8" UK Made

The Britool Hallmark MDB Deep AF Socket Range comprises original UK-manufactured 3/8" square drive hand sockets designed for professional automotive, engineering and mechanical applications requiring traditional AF / imperial fastener sizes.

Manufactured from high-quality Boron steel, each socket features a 12-point / bi-hexagon profile together with a deep-reach design, providing additional access to recessed fasteners and nuts positioned on longer threaded studs.

These MDB sockets were manufactured at the original Britool UK production facility before it closed. As remaining stocks are finite, individual sizes from this British-made range are becoming increasingly difficult to source.

Available in AF sizes ranging from 1/4" through to 7/8", these sockets are particularly useful for classic and vintage vehicle maintenance, older machinery, restoration projects and professional workshops continuing to work with imperial fasteners.

Key Features

• Genuine Britool Hallmark MDB Range
• Original Britool England / UK-manufactured sockets
• 3/8" square drive
• Deep / long-reach profile
• AF / imperial socket sizes
• Sizes available from 1/4" to 7/8" AF
• 12-point / bi-hexagon profile
• Manufactured from high-quality Boron steel
• Ball retaining groove in each face of the square drive
• Positive fit with compatible 3/8" drive accessories
• Professional hand-tool construction
• Ideal for classic automotive and engineering applications
• Increasingly rare original British-made tooling
• Individual sizes available
• Selected sizes available as the MDBSET9 9-piece set

AF / Imperial Size Range

Individual Britool MDB deep sockets are available in selected AF sizes from 1/4" through to 7/8".

Drive: 3/8" Square Drive
Socket Type: Deep / Long Reach
Profile: 12-Point / Bi-Hexagon
Measurement: AF / Imperial
Material: Boron Steel
Series: MDB
Manufacture: England / UK

Availability varies by size due to the age and discontinued nature of this original British-made range.

Please select the required AF size carefully when ordering.

Deep Socket Design

The deep profile provides additional reach compared with a conventional standard-depth socket.

This can be particularly useful when working with:

• Nuts positioned on longer threaded studs
• Recessed AF fasteners
• Engine components
• Classic vehicle assemblies
• Older machinery
• Agricultural equipment
• Mechanical and engineering applications

For mechanics maintaining older vehicles and machinery, a dedicated range of deep AF sockets provides useful imperial coverage alongside modern metric tooling.

12-Point Bi-Hexagon Profile

Each MDB socket features a 12-point / bi-hexagon profile for engagement with compatible AF fasteners.

The additional engagement positions can make socket alignment easier in restricted working areas, particularly where there is limited space available to reposition a ratchet or extension.

Always select the correct AF socket size and ensure full engagement with the fastener before applying torque.

Ball Retaining Grooves

Each socket incorporates a ball retaining groove in each face of the 3/8" square drive.

This provides a positive connection with compatible 3/8" drive ratchets, extension bars and hand-tool accessories, helping retain the socket securely during normal workshop use.

Original Britool England Manufacture

These MDB sockets were manufactured at the original Britool UK manufacturing facility before production there ceased.

As a result, the remaining sockets represent increasingly scarce examples of original British-manufactured Britool tooling.

They can be particularly relevant for:

• Classic British car mechanics
• Vintage vehicle restoration
• Classic motorcycle maintenance
• Professional automotive workshops
• Agricultural machinery repairs
• Mechanical engineering
• Older industrial machinery
• Existing Britool England tool users
• Britool tool collectors
• Customers replacing missing MDB sockets

Once remaining individual sizes have sold, availability of this original UK-made range may be limited.

Older UK Stock – Manufacturing Variations

Please be aware that these are older UK-manufactured sockets produced across differing manufacturing styles and production periods.

As a result, there may be some variation in finish, markings or general appearance between individual sockets.

These cosmetic and manufacturing variations do not alter the stated socket size or intended hand-tool application and are reflected in the reduced selling price.

This is particularly important for customers purchasing sockets to add to an existing older Britool collection, as an individual replacement may not be visually identical to another MDB socket already owned.

MDBSET9 9-Piece Set Available

For customers requiring a selection of popular AF sizes, selected MDB sockets are also available together as:

MDBSET9 – Britool England 9-Piece 3/8" Drive Deep AF 12-Point Socket Set

The MDBSET9 contains:

1/4", 5/16", 3/8", 7/16", 1/2", 19/32", 5/8", 11/16" and 3/4"

The set is supplied together on a socket rail.

Individual MDB sockets remain available separately according to remaining stock.

Professional Classic Automotive & Engineering Applications

AF / imperial fasteners continue to be encountered across many older vehicles, machinery and engineering applications.

Typical uses for the MDB range include:

• Classic British cars
• Vintage vehicles
• Classic motorcycles
• Vehicle restoration
• Older engines and machinery
• Agricultural machinery
• Mechanical engineering
• Professional garages
• Restoration workshops
• Industrial maintenance
• General imperial fastener applications

Always establish the correct fastener standard before selecting a socket, as AF, Whitworth and other imperial systems should not be treated as interchangeable solely because they appear similar in size.

Hand Tool Use Only

These are traditional chrome hand sockets designed for use with appropriate manual 3/8" drive tools.

They are not impact sockets and should not be used with:

• Pneumatic impact wrenches
• Cordless impact wrenches
• Electric impact tools
• Other powered impact equipment

The Britool Hallmark Range

The Britool Hallmark range was developed by Britool in the 1980s for the automotive aftermarket and has been a long-established choice for professional workshop users.

Each tool carries distinctive Britool Hallmark branding, ,  providing clear identification and reflecting the professional tooling heritage of the range.

The Britool Hallmark guarantee covers defects in materials and/or workmanship when tools are used for the purpose for which they were designed.

The guarantee does not extend to fair wear and tear or moving parts such as ratchet mechanisms.

Important Information

• This listing covers individual Britool MDB sockets in the selected size.
• Original Britool England / UK-made tooling.
• 3/8" square drive.
• Deep / long-reach socket profile.
• 12-point / bi-hexagon design.
• AF / imperial sizes from 1/4" to 7/8" subject to remaining stock.
• Manufactured from Boron steel.
• Older production means appearance and markings may vary between sockets.
• Cosmetic/manufacturing variations are reflected in the reduced price.
• Complete 9-piece selection also available as MDBSET9.
• Designed for hand-tool use only – not impact use.
• Product photograph is generic and may show a different size or manufacturing variation.
• You will receive the AF size selected when ordering.