Williams AV FM R37 Select FM Receiver with Surround EarphoneThe Williams Sound FM R37 includes a PPA R37N receiver, an EAR 022 surround earphone, and a pack of two AA batteries to power the unit. The receiver is compatible with all Williams Sound 72 76 MHz wide band transmitters and is designed to provide audio clarity and stability to help individuals with mild hearing loss overcome distance from the sound source. Williams Sound PPA R37 N Select Channel FM Receiver (No Earphone Batteries) The PPA R37 N Select