SMK-43 Wireless Smoke SensorBrand: NAVKAR SYSTEMS Color: White Model No: SMK 43 Features: Most Suitable to work with Wireless Security Alarm System The Sensor works on 9V Battery and the Battery needs to be Purchased Extra. 433 Mhz Wireless Security System is extra and not included with this Smoke Sensor. Sensor Wireless Frequency 433 Mhz Package Includes: 1 x Wireless Smoke Sensor (SMK 43)