VOCOPRO UL-580-4  Wireless lavalier System 4 Wireless Bodypacks Included with Lavalier Mics. 4 Independent XLR Mic Outputs 1 Mixed 1/4" Output. Individual Volume Controls for Precise Vocal Balancing. 4 Independent Field-Replaceable Receiver Modules. FCC Compliant UHF Band Operation. Rugged 1 RU Metal Receiver Chassis Fits 19" Racks. Bodypacks use 2 AA Batteries Each (not included)