Review on 🌡️ LayscoPro Mini Indoor Thermometer Hygrometer: 2-in-1 Analog Temperature Humidity Monitor Gauge - For Home, Room, Outdoor, Offices - Silver (2 Pack, Battery-Free) by Eliot Wahl

I waited a bit before rating this product. I'm mainly interested in its ability (or lack thereof) to accurately measure moisture inside a guitar case. My main concern is the reported five percent difference, give or take. I let all six cool for thirty-six hours, then calibrated them to the humidity level in the room as measured by our Nest thermostat. Luckily, the little beggars are accurate to within a few percentage points. I'm amazed that this modest price would even work, and even more so at the level I've been able to rely on in one of my guitar cases.