Chuango G3 GSM/SMS Alarm System Chuango G3 is an elegantly powerful alarm system that is easy to install and use. All it needs is a regular working 2G SIM card, and it can be armed/disarmed via a phone call or SMS text message from preauthorized phone numbers; preauthorized remote controls; or smartphone app commands. Upon detection of intrusion, the G3 will sound the built-in siren and call and/or text out to you for appropriate action. The intuitively designed Chuango G3 app interface enables you to effortlessly adjust system settings on the go: arm/disarm, home mode, remote voice memo or listening in. Chuango profile: Chuango Security Technology Corporation is an innovative manufacturer of electronic security products. Adhering to the brand promise of "Sincerity and Innovation" and associating with our deep comprehension of users' demands, we integrate the technology and design into people-oriented products to provide "easy-to-use" security products and solutions for global families and commercial clients.