hex key
Sign in to saveAlso known as Allen key, Allen wrench, Hex wrench, Unbrako, Inbus
tool for screws with an internal hex head.
~12 min read
Encyclopedic overview
Hex keys of various sizes
A hex key (also hex wrench, Allen key, Allen wrench) is a simple driver for bolts or screws that have heads with internal hexagonal recesses (sockets).
Excerpted from Wikipedia’s “hex key” article, available under the CC BY-SA 4.0 licence.