• Cole-Parmer Process grade thermometers are silicone-free • Greater temperature range• • Anti-parallax dial for accurate readings• Hermetically sealed per ASME B40.3 standard to prevent fogging and protect against tough environments• Rugged 304 stainless steel construction with a clear glass lens• Recalibrate using the external reset screw 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). | Measured stem length from the top of the threads to the bottom tip of the stem. Stem dia is 0.25\"; threaded connection is 1\/2\" NPT(M). All thermometers meet or exceed ASME B40.3 standards. | Maximum environmental temperature for glass lens thermometers is 500degF (148degC).| Discounts: Save 10% on 10-24 assorted thermometers, 15% on 25 to 49, and 20% on 50 or more.