Allen Wrenches - History, Use and Specifications

Allen Wrenches, or hex keys as they are commonly called, have been around since the mid 1800s but were made into the common wrench you see today by Allen Manufacturing Company out of Connecticut in the early 1900s. Allen Wrench is the six-sided L-shaped wrench used to drive hexagon recessed socket screws.
Quick history on Allen Wrenches (Hex Keys) with common uses, benefits and specifications.

About Allen Wrench – DEKO Tools

Folding Hex Wrench Metal Metric Allen Wrench set Hexagonal Screwdriver Hex Key Wrenches Allen Keys Hand Tool Portable set with - Price history & Review

Monster Bolts - Fastener news

Allen Manufacturing Company

The History of the Allen Wrench - Garden Guides

All about the Allen key

How is an Allen wrench used?

Allen vs Allen The Garage Journal

A brief history of Hexagon and Torx Keys - Wonkee Donkee Tools

Everything You Need To Know About Hex Key Sets

Allen Hex Key L Type Wrench Fastener Bolt Nut Hand Tools - China Allen Hex Key, L Type Wrench

Wrench, Types, Uses & Maintenance

Hex key - Wikipedia

MULWARK 17pcs Folding Allen Wrench Set | Metric & Standard SAE - Key Tool 2 Pack Portable Hex for Basic Home Repair and General Applications

Titanium non-magnetic imperial (inch) hex (Allen) key kit large version - Imprex International, Inc.

Mastercraft SAE/Metric Folding Hex Key Set/Allen Wrench Set, Rust Resistant, Cr-V Steel, 3-pk

Strandberg Allen Key Kit for Bridge, Tunning, and Truss Rod