Tango™ TX1 Single gas detector with revolutionary DualSense® Technology, includes two of the same type sensor. DualSense® Technology increases worker safety, regardless of bump test frequency, while reducing overall costs. The Tango has a three year warranty which does not include battery, sensors and filters. The CO and H2S sensors are warranted for 3 years from the initial purchase date. All other sensors are warranted for 2 years from the initial purchase date.