Yield Lab Digital Thermo-Hygrometer AN ESSENTIAL TOOL: Our digital thermo-hygrometer provides a large, easy-to-read digital display for the current temperature and humidity in an all-in-one compact unit. READY TO GO: No complicated setup or installation. Choose between the magnetic backing or foldout kickstand: whichever works best for your indoor growing system. CONVENIENT FEATURES: Includes a clock and calendar (month and date) function for multipurpose functionality. KEEP IT NEAT: Dont add cords or bulky extras to your system. This is a wireless unit powered by 1 AA battery, and it measures just 2.5 x 3 inches. DISPLAY EVERYTHING: Get all the information you need in one glance; it displays temperature, humidity, and time simultaneously.