United Scientific Supplies, THTC02, Thermometer, Red Liquid, 12", Total Immersion, -10°C to 150°C
Red spirit-filled thermometer provide increased safety and economic pricing. It contain a petroleum-based column with red dye, which is significantly safer than mercury.
Full immersion thermometer need to be submerged deep enough so the desired temperature is at the meniscus. For example, if you wish to measure the temperature of a hot water bath to make sure it is 100°C, then you need to submerge the thermometer up to the 100°C mark.