Wireless Vehicle Alert Optex Wireless 2000 Annunciator System $179.95 Additional Wireless Drive-up Sensor for Optex 2000 Annunciator System $84.95 Additional Voice Alert Transmitter or Sensor $54.95 Wireless Voice Alert System $124.95 Optex Wireless 1000 Repeater $139.95 Optex Wireless 2000 Chime Box With Relay $94.95