Features : * 4 Wire smoke detector relay output  * Compatible with all security alarm systems  * Alarm relay output N.O/N.C contacts  * Two flashing LED's provide 360 degree visibility  * Un-polarized wire input  * Wide range of operating voltage 9-28VDC  * Unique optical sensing chamber  * Built in microprocessor and intelligent software  * Insect-resistant screening  * Twist-on mounting bracket with tamper lock  * Drift compensation and smoothing algorithms  * Includes base  * 1 year warranty .     Model : IDS862-12-SD142     Manufacturer : IDS