Shure GLXD16 Digital Guitar Pedal Wireless System, Z2 Includes: (1) GLXD6 Wireless Guitar Pedal Tuner and Receiver, (1) GLXD1 Wireless Bodypack Transmitter, (1) WA305 Locking-thread Guitar Cable, (1) SB902 Rechargeable Lithium-Ion Battery, (1) PS23US Power Supply and (1) SBC-USB-MicroB Wall Battery Charger Operate up to 4 compatible systems in typical setting, up to 8 maximum under ideal conditions Best-in-class intelligent lithium-ion battery rechargeability allows up to 16 hours of continuous use and greatly reduces the cost of ownership LINKFREQ Automatic Frequency Management Intelligent frequency management quickly identifies the best open frequencies