The ATR1, K-type thermocouple is perfect for testing the temperature of air flowing through ductwork. The long rod can reach the middle of ducts for accurate air temperature readings of the entire cross-section. The large handle gives the HVAC/R technician the leverage to push the sharp tip through soft ducts. The ATR1 can be used with any of our meters that measure temperature and any thermometer accepting a K-type thermocouple.