The SPK2 Folding Pocket Thermometer is great for taking quick air temperatures. It fits directly in your pocket so you're ready for common temperature checking. The folding rod has a hanging hook so you can easily hang it in a duct or on a grille. The large display shows Min/Max/Hold, has measurements in both Fahrenheit and Celsius, and has a low battery indicator. The SPK-2 also quickly calculates T1-T2 temperature classes, as well as features an Auto Power Off function to save battery power on it's already phenomenal 8,000 hours of battery life on one single AA battery!