gsm remote wireless door sensor with smart sensor

gsm remote wireless door sensor with smart sensor Skype: lisali1220 QQ: 2946370755 WhatsApp:0086 13652426178 HOME IS ON THE PHONE W20 smart GSM alarm system is composed by series of smart devices, such as: GSM host, smart wireless sensors, Wi-Fi camera. It designed for home/commerce/office area, etc. W20 users can directly interact with the system via Mobile Phone APP. Besides, users can master the monitoring site anytime and anywhere. W20 security functions includes: sending