Genius Tools 3/8 Drive Metric Hex Allen Bit Socket Range, 3-12mm

The Genius Tools 3/8" Drive Metric Hexagon Bit Sockets are professional-quality Allen key socket bits designed for loosening and tightening metric internal hexagon fasteners using suitable manually operated socket tools.

Available in individual sizes from 3mm to 12mm, these hex bit sockets combine a precision-fitting hexagon bit with a 3/8" square drive socket body, allowing technicians to use ratchets, extension bars and other compatible hand-operated drive tools.

With an overall length of approximately 50mm, the sockets offer a practical balance between accessibility, control and compact dimensions for general automotive, engineering and mechanical maintenance applications.

These sockets are suitable for working with metric hex socket head screws, Allen bolts, recessed hexagon fasteners and other compatible internal hexagon fittings.

The range includes 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12mm sizes, providing a useful selection for professional mechanics, maintenance engineers, machinery technicians and home workshop users.

Each socket is designed for manual hand tool operation only.

Important: These are not impact-rated hex bit sockets and must not be used with pneumatic, cordless or electric impact tools.

Replacement hex bits are available separately, allowing worn or damaged consumable bits to be replaced where compatible.

Key Features

• Genuine Genius Tools professional hexagon bit sockets
• 3/8" square drive
• Metric hexagon / Allen bit profile
• Available in sizes 3mm to 12mm
• 10 individual metric sizes available
• Overall length approximately 50mm
• Designed for manual hand tool use
• Compatible with suitable 3/8" drive hand ratchets
• Compatible with suitable 3/8" drive extension bars
• Suitable for manually operated breaker bars and other compatible drive accessories
• Designed for internal hexagon socket fasteners
• Useful for automotive, mechanical and engineering applications
• Compact socket design for practical workshop use
• Different bit shank configurations according to socket size
• Replacement hex bits available separately
• Individual bits are classified as consumable components
• Not suitable for powered impact tool use

Available Metric Hexagon Socket Sizes

The Genius Tools 3/8" Drive Metric Hexagon Bit Socket range is available in the following individual sizes:

• 3mm Hexagon / Allen Bit Socket
• 4mm Hexagon / Allen Bit Socket
• 5mm Hexagon / Allen Bit Socket
• 6mm Hexagon / Allen Bit Socket
• 7mm Hexagon / Allen Bit Socket
• 8mm Hexagon / Allen Bit Socket
• 9mm Hexagon / Allen Bit Socket
• 10mm Hexagon / Allen Bit Socket
• 11mm Hexagon / Allen Bit Socket
• 12mm Hexagon / Allen Bit Socket

Please select the required size from the available product options.

These sizes refer to the metric hexagon bit tip, not the square drive size.

All versions use a 3/8" square drive connection.

3/8" Square Drive Compatibility

Each Genius Tools hex bit socket features a 3/8" square drive, making it suitable for use with compatible manually operated socket tooling.

The 3/8" drive format is widely used in professional automotive and engineering workshops because it provides a useful combination of manageable tool dimensions and controlled manual operation.

Suitable hand tools include:

• 3/8" drive hand ratchets
• 3/8" drive extension bars
• 3/8" drive sliding T-handles
• 3/8" drive manual breaker bars
• Other suitable manually operated 3/8" drive accessories

The correct socket size and suitable hand tool should always be selected for the application.

Metric Hexagon / Allen Bit Profile

These sockets are designed to engage metric internal hexagon fasteners, commonly referred to as Allen bolts or hex socket screws.

The hexagon bit fits into the internal recess of a compatible fastener, allowing torque to be applied using a suitable hand-operated socket tool.

This design is useful for mechanical assemblies where a conventional external hexagon socket or spanner cannot engage the fastener.

Typical applications include socket head cap screws, machinery fasteners, automotive components and workshop equipment.

For best results, always ensure that the bit is fully inserted into the fastener recess before applying torque.

A poorly fitting or partially engaged bit can damage both the tool and the fastener.

Approximately 50mm Overall Length

Each socket has an overall length of approximately 50mm.

This compact length makes the range suitable for many general servicing and maintenance applications where a long-reach hex bit socket is unnecessary.

The overall design allows the socket to be used with compatible extension bars when additional reach is required.

The approximately 50mm length refers to the complete socket assembly, including the hexagon bit and socket body.

Hex Bit Shank Sizes

The Genius Tools range uses different hex bit shank dimensions depending on the selected metric bit size.

These shank measurements describe the bit section fitted into the socket body, not the 3/8" square drive connection.

3mm, 4mm, 5mm and 6mm Hex Bits

The 3mm, 4mm, 5mm and 6mm hex bit sockets use bits with a 1/4" shank.

7mm and 8mm Hex Bits

The 7mm and 8mm hex bit sockets use bits with a 5/16" shank, as specified in the supplied product information.

9mm, 10mm, 11mm and 12mm Hex Bits

The 9mm, 10mm, 11mm and 12mm hex bit sockets use a shank corresponding to the nominal hex bit size.

These differences are important when identifying suitable replacement bits.

Always confirm the correct bit size and shank configuration before purchasing replacement components.

Hand Use Only – Not Impact Rated

The Genius Tools metric hex bit sockets in this range are specifically intended for manual hand tool operation.

They are not designed for use with impact wrenches or impact drivers.

Powered impact equipment subjects tools to repeated shock loading, which can damage hex bit sockets that are not designed or rated for impact applications.

For this reason, these sockets must not be used with:

• Pneumatic impact wrenches
• Cordless impact wrenches
• Electric impact wrenches
• Impact drivers
• Other powered impact fastening equipment

For impact applications, use a specifically designated impact-rated hex bit socket suitable for the intended tool and fastener.

Replacement Hex Bits Available Separately

Replacement Genius Tools hexagon bits are available separately for compatible sockets in this range.

This is useful for workshops where certain sizes are used frequently or where a bit becomes worn or damaged during service.

Instead of replacing the complete socket assembly, the appropriate replacement bit may be purchased separately.

Replacement bits must match the required hexagon tip size and shank configuration.

Genius Tools classifies replacement bits as consumable components, and they are excluded from the manufacturer's standard warranty coverage.

This does not affect applicable statutory consumer rights.

Available as Full 10 Piece Set

All sizes are available as a 10 piece set, BS-310HM, if preferred.

One of each size is supplied on a tool rail.

Professional Automotive and Engineering Applications

The Genius Tools 3/8" Drive Metric Hexagon Bit Sockets are suitable for:

• Automotive servicing and repairs
• Engine component maintenance
• Brake component servicing where suitable
• Motorcycle maintenance
• Mechanical assembly work
• Machinery maintenance
• Engineering workshops
• Industrial equipment servicing
• Agricultural machinery maintenance
• Plant equipment maintenance
• Vehicle restoration
• General mechanical repairs
• Socket head cap screw installation and removal
• Internal hexagon fastener maintenance
• Professional garages
• Home workshop use

These applications require appropriate manually operated tooling and correctly sized fasteners.

Technical Specifications

• Brand: Genius Tools
• Product type: Metric Hexagon / Allen Bit Socket
• Drive size: 3/8" square drive
• Drive operation: Manual hand use only
• Measurement system: Metric
• Bit profile: Internal hexagon / Allen
• Available sizes: 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12mm
• Number of available sizes: 10
• Overall socket length: Approximately 50mm
• 3mm bit shank: 1/4"
• 4mm bit shank: 1/4"
• 5mm bit shank: 1/4"
• 6mm bit shank: 1/4"
• 7mm bit shank: 5/16"
• 8mm bit shank: 5/16"
• 9mm bit shank: Same nominal size as bit
• 10mm bit shank: Same nominal size as bit
• 11mm bit shank: Same nominal size as bit
• 12mm bit shank: Same nominal size as bit
• Impact rated: No
• Suitable for powered impact tools: No
• Replacement bits: Available separately
• Replacement bit classification: Consumable component
• Primary applications: Automotive, engineering and mechanical hand tool use
• Material specification: S2 High Speed Steel

About Genius Tools

Genius Tools is a Canadian professional tool brand with an established reputation in the automotive and industrial tooling markets.

The brand is well known throughout Canada and the United States for its range of professional hand tools, socket sets and specialist workshop equipment.

Genius Tools products are also available in the UK and European markets, providing professional mechanics and engineers with a broad selection of workshop tooling.

The Genius Tools range includes sockets, ratchets, spanners, impact tooling, specialist automotive equipment and tool storage solutions.

These 3/8" drive metric hexagon bit sockets are designed to provide practical solutions for everyday mechanical fastening applications using professional hand tools.

Genius Tools Warranty

Most Genius Tools branded products are covered by a manufacturer's warranty against defects in materials and workmanship for the expected usable life of the product, subject to the applicable warranty terms and conditions.

Where a qualifying manufacturing or material defect is identified, the manufacturer may repair or replace the product following inspection.

The manufacturer's warranty does not generally cover:

• Misuse or incorrect application
• Fair wear and tear
• Damage caused by overloading
• Use with impact tools where not permitted
• Striking tools
• Consumable tools and components
• Replacement bits
• Spare parts and other excluded maintenance components

Important: Replacement hexagon bits are classified by Genius Tools as consumable items and are not covered by the manufacturer's standard warranty.

Full Genius Tools warranty terms and conditions apply.

These terms do not affect applicable statutory consumer rights.

Important Information

• Genuine Genius Tools 3/8" drive metric hexagon bit sockets
• Available in individual sizes 3mm to 12mm
• Please select the required size
• Approximately 50mm overall length
• 3/8" square drive on all sizes
• Designed for manual hand tool use only
• Not impact rated
• Do not use with pneumatic, cordless or electric impact tools
• Different bit shank sizes apply across the range
• Replacement bits available separately
• Replacement bits are classified as consumables and excluded from the manufacturer's standard warranty
• Always use the correct metric hex bit size
• Ensure the bit is fully engaged with the fastener before applying torque
• Avoid excessive force and sideways loading
• Do not use worn, rounded or damaged hex bits
• Check the fastener manufacturer's torque requirements where applicable
• This listing is for Genius Tools 3/8" Drive Metric Hexagon / Allen Bit Sockets in the selected individual size.
• If 10 piece set is required please review Genius set part reference of BS-310HM