2GIG?s Wireless Smoke/Heat/Freeze Alarm is a 3xAAA battery?powered wireless alarm intended for use in a 2GIG system. The alarm has a built?in wireless transmitter, which communicates with the 2GIG Control Panel. When smoke, excessive heat or cold is detected, the alarm sounds a loud local alarm and the built?in transmitter sends a signal to the Control Panel. This alarm is designed to provide protection within a 35?foot radius of the unit. The 2GIG?SMTK3?345 can send alarm, tamper and battery condition messages to the Control Panel.