Sennheiser EW-D SK Q1-6 - Digital pocket transmitter for EW-D wireless systems, frequency range Q1-6: 470.2 - 526 MHz, transmit power: 10 mW, operation with 2x AA batteries or optional BA70 rechargeable battery, dimensions (WxHxD): 63 x 80 x 20 mm, weight: 120 g