The PPA R35-8 FM receiver can operate up to eight channels simultaneously when used with any Williams Sound Personal PA transmitter operating on the 72-76 MHz bandwidth. The PPA R35-8 features crystal clear audio, and is digitally synthesized for stable tuning. Each unit is built in a rugged impact-resistant case, and and will operate up to 50 long-lasting hours on two AA alkaline batteries (not included). It also features an integral volume on/off control, LED power and low battery indicator, channel selection knob and earphone jack. When AA NiMH rechargeable batteries are installed (not included), up to 12 units can be charged at one time when used with the optional CHG 3512 multi-charger. The PPA R35-8 FM receiver is covered by Lifetime PLUS Limited Warranty.