Metric Hex Keys

Metric hex keys, commonly known as metric Allen wrenches or metric Allen keys, are precision tools designed for installing and removing metric socket head cap screws, metric socket set screws, metric button head socket cap screws, metric flat head socket cap screws, metric shoulder screws, and other internally driven fasteners. Their compact L-shaped design provides access to recessed fasteners in applications where conventional wrenches or sockets cannot be used.

Metric hex keys are commonly used throughout industrial machinery, automation equipment, robotics, manufacturing equipment, tooling, fixtures, maintenance departments, machine shops, production facilities, OEM manufacturing, and field service operations. They are an essential tool for assembling, servicing, and maintaining equipment utilizing metric internal hex fasteners.

Proper tool selection should consider the required metric hex size, available installation clearance, fastener accessibility, and application requirements. Individual product pages provide verified metric hex key sizes and dimensional information where available to assist engineers, maintenance professionals, and purchasing teams in selecting the appropriate tool.

Cold Headers supplies metric hex keys in a broad range of metric sizes for use with metric socket head cap screws, button head socket cap screws, flat head socket cap screws, socket set screws, shoulder screws, and other internally driven fasteners. Our catalog is organized to simplify exact-size selection while providing consistent engineering information across every product family.

Why Choose Metric Hex Keys?

  • Designed for metric internal hex fasteners: Suitable for metric socket head cap screws, socket set screws, button head, flat head, and shoulder screws.
  • L-shaped design: Provides access to recessed fasteners in confined spaces.
  • Industrial applications: Commonly used in manufacturing, maintenance, automation, robotics, tooling, and OEM production.
  • Serviceable design: Suitable for assembly, maintenance, repair, and equipment servicing.
  • Verified sizing: Product pages provide metric hex key size information where available.

Selecting the Correct Metric Hex Key

Begin by confirming the required metric hex size for the mating fastener. Review installation clearance, fastener accessibility, tool length, and application requirements before selecting a hex key. Proper tool selection helps ensure efficient installation and maintenance of internally driven metric fasteners.

Cold Headers Inc. has supplied specialty industrial fasteners and related products since 1962. Our catalog helps engineers, distributors, maintenance professionals, and purchasing teams locate exact metric sizes and difficult-to-find industrial fastening products without unsupported inventory claims.

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.

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Unit of Measure
Items
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1.5 mm Metric Hex Key
List Price (per 100 pieces) $20.00
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2 mm Metric Hex Key
List Price (per 100 pieces) $22.50
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2.5 mm Metric Hex Key
List Price (per 100 pieces) $25.00
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3 mm Metric Hex Key
List Price (per 100 pieces) $28.75
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4 mm Metric Hex Key
List Price (per 100 pieces) $32.50
Description N/A

1.5 mm Metric Hex Key is a loose metric hex key for socket-drive work where the exact 1.5 mm width is called out on the print. The ISO 2936 width band is 1.50 / 1.48 mm, sized just under nominal so the key can enter an in-tolerance socket and bear on the flats.

Metric machinery maintenance benefits from loose replacement keys because a single lost driver can stall the repair. This family supports the metric side of the catalog, including socket-drive cap screws, flat heads, buttons, shoulders, and set screws.

Review the 1.5 mm size and ISO 2936 max/min width data against the print before ordering. Keeping the driver as a loose single size helps replace the exact tool without buying a full set. The technical highlights below keep the verified width data separate from general application notes.

Technical Highlights

  • Style: L-shaped metric hex key
  • Width Across Flats: 1.5 mm (1.50 / 1.48 mm)
  • Drives: drives M3 metric socket set screws
  • Dimensional Standard: ISO 2936

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.

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2 mm Metric Hex Key fills the 2 mm driver position for metric socket fasteners maintained in crib quantities. The ISO 2936 width band is 2.00 / 1.96 mm, sized just under nominal so the key can enter an in-tolerance socket and bear on the flats.

Tool cribs replenishing loose metric sizes can avoid buying complete sets just to replace one driver. This family supports the metric side of the catalog, including socket-drive cap screws, flat heads, buttons, shoulders, and set screws.

Review the 2 mm size and ISO 2936 max/min width data against the print before ordering. Keeping the driver as a loose single size helps replace the exact tool without buying a full set. The technical highlights below keep the verified width data separate from general application notes.

Technical Highlights

  • Style: L-shaped metric hex key
  • Width Across Flats: 2 mm (2.00 / 1.96 mm)
  • Drives: drives M4 metric socket set screws
  • Dimensional Standard: ISO 2936

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.

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2.5 mm Metric Hex Key supports imported machinery service when the equipment print calls for a single metric driver size. The ISO 2936 width band is 2.50 / 2.46 mm, sized just under nominal so the key can enter an in-tolerance socket and bear on the flats.

Field service carts use individual metric keys for panels, machine covers, and socket hardware on imported systems. This family supports the metric side of the catalog, including socket-drive cap screws, flat heads, buttons, shoulders, and set screws.

Review the 2.5 mm size and ISO 2936 max/min width data against the print before ordering. Keeping the driver as a loose single size helps replace the exact tool without buying a full set. The technical highlights below keep the verified width data separate from general application notes.

Technical Highlights

  • Style: L-shaped metric hex key
  • Width Across Flats: 2.5 mm (2.50 / 2.46 mm)
  • Drives: drives M3 metric socket head cap screws and M5 set screws
  • Dimensional Standard: ISO 2936

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.

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3 mm Metric Hex Key gives assembly teams a dedicated 3 mm L-key instead of another mixed-size kit on the bench. The ISO 2936 width band is 3.00 / 2.96 mm, sized just under nominal so the key can enter an in-tolerance socket and bear on the flats.

Imported equipment service often depends on metric tools at the machine rather than inch substitutes from a nearby bench. This family supports the metric side of the catalog, including socket-drive cap screws, flat heads, buttons, shoulders, and set screws.

Review the 3 mm size and ISO 2936 max/min width data against the print before ordering. Keeping the driver as a loose single size helps replace the exact tool without buying a full set. The technical highlights below keep the verified width data separate from general application notes.

Technical Highlights

  • Style: L-shaped metric hex key
  • Width Across Flats: 3 mm (3.00 / 2.96 mm)
  • Drives: drives M4 metric cap screws and M6 set screws
  • Dimensional Standard: ISO 2936

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.

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4 mm Metric Hex Key helps replace a rounded or missing metric key before the socket in the fastener is damaged. The ISO 2936 width band is 4.00 / 3.95 mm, sized just under nominal so the key can enter an in-tolerance socket and bear on the flats.

Robotics and automation cells commonly keep dedicated metric keys near guards, tooling, sensors, and changeover points. This family supports the metric side of the catalog, including socket-drive cap screws, flat heads, buttons, shoulders, and set screws.

Review the 4 mm size and ISO 2936 max/min width data against the print before ordering. Keeping the driver as a loose single size helps replace the exact tool without buying a full set. The technical highlights below keep the verified width data separate from general application notes.

Technical Highlights

  • Style: L-shaped metric hex key
  • Width Across Flats: 4 mm (4.00 / 3.95 mm)
  • Drives: drives M5 metric cap screws and M8 set screws
  • Dimensional Standard: ISO 2936

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.
Brands N/A Cold Headers, Inc.
Size N/A 1.5 mm N/A 2 mm N/A 2.5 mm N/A 3 mm N/A 4 mm
Quantity N/A 100
Package Type N/A Box
Note N/A Less Than Package Quantity Specified Plus 25%.