Review on 🌡️ Inkbird ITH-10 Digital Thermometer Hygrometer Temperature Humidity Monitor for Humidors, Guitars, Ukuleles, and Mason Jars. by Daniel Drury

This isn't the most expensive hygrometer, but as far as I can tell it's accurate. It reads the temperature accurately and successfully passed the "salt test" after 20 hours, the last 4 of which were completely stable at 75%. Throw it in a guitar case and it leveled off within 3 hours and hasn't changed from 70 degrees, 49% RH. Exactly what I wanted, a great option for a guitar case, in my opinion, no need to spend more.