... switch - Quad band GSM-850, GSM-900, GSM-1800, GSM-1900 MHz - 2 outputs GSM remote control switch The GSM-RKEY remote Controller suitable for below ... by sending back a text message. · Quad band GSM-850, GSM-900, GSM-1800, GSM-1900 MHz so will work anywhere in the world ... that has a GSM phone networkTwo independent relays that can ...