Please note the following points when soldering using a soldering iron.
After sufficient preheating (150°C for 1 to 2 minutes.), use a trowel with φ3mm or less and 30W or less, and solder within 5 seconds at 350°C or less. Use a flux of 0.1wt% or less of halogenated substances. Also, please do not touch the ceramic body directly.