Sony's ECM-HW2 wireless microphone is the world's first interactive communication equipment for video cameras, with terminals on both microphone & receiver. You & the subject can talk back & forth, laugh, joke, sing, & share all the fun while filming & recording. With the Bluetooth wireless technology, ECM-HW2 picks up every word or note with sound clarity at distances up to 100 meters. By simply attaching the receiver to Sony Handycam's Active Interface Shoe, you can enjoy wireless microphone performance for truly versatile recording. The energy-saving ECM-HW2 matches the recording time of the previous model, but requires only half the battery capacity, successfully enabling smaller & lighter microphone design. ECM-HW2 doesn't get in the way of movement, & the wearer isn't conscious of the microphone, for natural, spontaneous behavior.