System Sensor 2WT-B Smoke & Thermal 2 WireThe 2WT B is a 2 wire, photoelectric i3 smoke detector with a 135F fixed thermal sensor. Standard conventional 2 wire System Sensor, System Sensor 2WT B Smoke & Thermal 2 Wire Detector The System Sensor 2WT B Smoke & Thermal 2 Wire Detector is designed to provide advanced security and safety. Its a high performance smoke and thermal detector that integrates seamlessly into your existing alarm system. This device ensures the highest levels of