This Sennheiser EW-D ME3 SET Digital Wireless Headset System is perfect for those who speak or present on stage. The bodypack transmitter has a metal housing, and the clip-on microphone ME 3 (cardioid) offers high speech intelligibility. It features digital transmission in the UHF spectrum for enhanced range. The Smart Assist App allows for seamless pairing and management via Bluetooth Low Energy. With auto scan, reliable connections are made easily. The system has a 134 dB audio input dynamic range. Channels can be placed 600 kHz apart. It has 56 MHz of tuning bandwidth and up to 90 channels with 2,240 selectable frequencies. The lithium-ion battery pack (sold separately) gives up to 12 hours of operation (8 hours with 2x provided AA batteries). The bodypack transmitter dimensions are 212 x 44 x 189 mm and weighs approx. 1000 g (without antennas and power supply). The ME 3 microphone has a 3.5 mm jack, frequency response of 50 to 18,000 Hz, max sound pressure level of 150 dB, cable length of approx. 1.60 m, and a cardioid pick-up pattern.