Allen key

Allen + key, from the name of the Allen Manufacturing Company.

• IPA^(key): /ˈælən kiː/

Allen key (plural Allen keys)

2. Synonym of hex head wrench.

• Allen screw
• Allen bolt

• “Allen key”, in Collins English Dictionary.
• “Allen key”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.
• “Allen key”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.
• “Allen key”, in Cambridge English Dictionary, Cambridge, Cambridgeshire: Cambridge University Press, 1999–present.

• alkylene