紅外 hongˊ waiˋ

(Infrared)

Infrared

外線 waiˋ xianˋ

(Contact, External)

External line, Contact outside of a secret group

紅

Red, Work, Worker, Working

Red, (Gong1), Work, Working, Worker

外

External, Foreign, In Addition, Outside

Outside, External, Foreign, In Addition

線

Circuit, Clue, Line, Path, Thread

Line, Thread, Path, Clue, Circuit