Audible Bat SignalsBatman's ears are on the inside of his costume.
Have you ever wondered how he hears bad guys coming (or what he's listening to during all those fight scenes?) He might wear a pair of these Batman Bluetooth Kid's Heatphones. DC Comics Batman Youth Bluetooth Headphones | Batman Gifts The speakers have a rechargeable battery that lasts for up to 24 hours, and a built-in microphone, for mid-fight chats with Alfred..