• 850/900/1800/1900MHz quad bands, can work in the worldwide GSM networks.

• No call charges. The GSM Relay Switch answers the call from authorized number then carries out the turn ON/OFF action on the first 'ring'.

• Secure - Using caller-ID for identification, unknown callers are ignored.

• Add or remove users by SMS Text command.

• No need to provide a remote control or keys for different users.