Agent 66 calls CONTROL on her bra phone.
Wearable communications device.
The user speaks into one cup and listens on the other.
[GS95 Episode #7: "Liver Let Die".]
CONTROL Agent 66 has one but Agent 9 is still waiting for her training bra phone.
[Mentioned, GS95 Episode #6: "Wurst Enemies".]
See also "Bullet Bra".