HOT!Home use gas detector with shut off valve 1,ISO9001&CE 2,In the house and close the gas valve 3,Alarm,security HOT!Home use gas detector with shut off valve Features:Adopts nanotechnology sensor with self-design patented technology, low false alarm.Network signal: NO, NC and LEVEL can use the network signal to start up the fans.Fit for using together with many low voltage control system ( ...