The Extech 44550 is a pen style humidity and temperature meter. It features a dual LCD for simultaneous display of relative humidity and temperature (°C/°F switchable). This temperature pen measures humidity from 20% RH to 90% RH ± 5% RH and temperature from -10°C to 50°C ± 1°C (14°F to 122°F ± 2°F). It is pocket sized for quick and reliable measurements at any location. The max/min memory functions for display of highest and lowest readings for both measurements. Complete with pocket clip and one LR44 button battery.