zeta key vs Unbrako key

zeta key and Unbrako key both are nouns.

Word	Noun	Adjective	Verb	Adverb
zeta key	Yes	No	No	No
Unbrako key	Yes	No	No	No

As nouns, zeta key and Unbrako key are synonyms defined as:

Other synonyms of zeta key include Allen key, hex key, Inbus key, Inbus wrench, Unbrako wrench, zeta wrench.

zeta key (noun)	Unbrako key (noun)
a wrench for Allen screws	a wrench for Allen screws