1.GSM Alarm System with relay output 2. Got CE/FCC/CCC 3 ... introduction:This product is the GSM auto-dial alarm system. The system will call 5 users’ numbers + room number and ... warehouses, orchards, factory floors ,etc.Business/Home GSM Alarm System with:1.GSM 900/1800/1900 bands , can be used ... siren, 2 remote controllers, 1 power supply, 1 manual Hot selling GSM Alarm System with relay output (M3B)