The PSM®900 Wireless Personal Monitor System from Shure offers an unprecedented combination of superb audio quality, robust RF performance, and category-leading features for the most demanding professional applications. All new, patent-pending CueMode allows the sound engineer to monitor different stage mixes with the touch of a button. Precision front-end RF filtering significantly reduces dropouts from RF interference, and the enhanced digital stereo encoder provides excellent stereo separation and audio clarity. Please note: the SBC200 charger, SBC800-US charger, and SB900 rechargeable battery are available separately. They are not included in P9TRA425CL and P9TRA systems.