Webster's Revised Unabridged Dictionary · 1913

all-mains

all-mains , adjective, prenominal

For power supplies, the term "switching" is used to designate ability to use more than one voltage as a power source. Typically, it is used for the ability to use both 110 and 220 volt AC sources.

1.
adaptable to all voltages; -- of a radio receiver. [British]