product features:

Now a full function electronic flag set at half the price of current Signal Bip flags. Set includes two flags for the assistant
referees, an arm receiver for the referee in the middle and a distinctive set of OSI checkered flags plus flag case. All OSI
swivel flags will fit on these poles. The receiver can be set for sound only, vibration only or for both sound and vibration.
Easy to use and each component takes a standard 9V battery. A set of three batteries is included with each set.