Six’s Thermometer is a registering thermometer used to record the maximum and minimum temperatures over a set period, usually 24 hours. It shows the current temperature along with the highest and lowest values since the last reset. This thermometer is used in laboratories, weather stations, schools, and environmental studies. Its U-shaped glass tube, dual scales, and mercury indicator section offer clear and reliable readings. The design supports accurate temperature monitoring and simple resetting using a magnet.