The Cole-Parmer® industrial bimetal thermometers feature NEMA 4X/IP66 protection for tough applications. Accuracy is ±1% full-scale when stem is immersed 2" in liquids or 4" in gases (immerse models with a 2.5" stem length 2" in gases). Stem length is measured from the top of the threads to the bottom of the stem tip. Stem diameter is 0.25” with a ½” NPT(M) back connection. Maximum overtemperature for thermometers with a max temperature of 250°F is 100% of span, and thermometers with a max temperature of 550°F is 50% of span. The ambient temperature range limits are –40 to 200°F (–40 to 93°C).