8 Channel GSM Alarm System with Battery Backup App Control SMS Alert for Home Security Battery-controlled, low-power alarm.Wide input voltage supply from 5 V DC to 15 V DC. Each alarm can be configured with different contents independently. SMS be sent to a maximum of 6 pre-installed mobile phones when any alarm is triggered. Fully 8 input signals and you can select the input port as NC or without mode for signaling. It is used in home security, warehouse security, remote unmanned areas, security. Specification: Condition Colour:black Material:ABS plastic Size:66 * 62 * 22mm Package Contents: 1 * GSM Alarm 1 * Antenna 1 * Cable Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.