Answer:

earpiece

Answer	Crossword Clue
EARPIECE	Spy's aid
EARPIECE	Cap part
EARPIECE	Eyeglasses part

EARPIECE	Audio accessory
EARPIECE	Operator's need
EARPIECE	Secret Service agent's accouterment
EARPIECE	Standard-issue item for a Secret Service agent
EARPIECE	Listen here!
EARPIECE	Hearing aid part
EARPIECE	Phone part
EARPIECE	Cell phone accessory

EARPIECE	Part of a hearing aid