The SOS GateTrigger is a dual system. It will open a gate for an emergency vehicles siren and it will open to RFID tags. The tags are used by the home owner, employees or trucks. The range for the RFID tags is adjustable up to 600 feet.
The SOS-Silent is used in municipalities that are requiring it. It is a dual system that allows emergency vehicles to open the gate with the RFID tag mounted on the their vehicle. If they do not have a tag they can open the gates with their siren.