Audio-Technica System 10 Handheld, digital 2,4 GHz Wireless System, 24 Bit/48 KHz, three modes to get a better signal: frequency, time and room diversity, automatic frequency setup, up to 8 systems parallel, incl. handheld transmitter with dynamic capsule, 10 mW transmitted power, works with 2x 1,5V AA batteries (not including), 20 - 20.000 Hz, incl. microphone clamp AT8456a and powersupply, licenced free all over the world