Shure ULX-D Wireless Dual channel Receiver. Includes two Beta58 Handheld microphones and two ULXD1 beltpack transmitters with WL184 cardioid elements. ULX-D Digital Wireless Systems ULX-D® Digital Wireless offers extremely efficient RF performance, networked control, Dante™ digital audio, and AES-256 encryption for professional sound reinforcement. Includes Shure SB900 Lithium-Ion Rechargeable Battery Up to 64 MHz overall tuning bandwidth (region dependent) Up to 47 active transmitters in one 6 MHz TV channel (63 in one 8 MHz TV channel) in High Density mode