Govee Bluetooth Hygrometer Thermometer, Wireless Thermometer, Mini Humidity Sensor with Notification Alert, Data Storage and Export, 262 Feet Connecting Range, 3 Pack

You can get a three-pack of Govee sensors for less than the price of one Ruuvitag, and they're smaller. I have one in my fridge, one in the RV cabin, and one in the truck. I'm going to get more for my power systems cabinet and for outside the RV. Bluetooth-capable with a phone app. I monitor mine via Home Assistant instead. Good range on the Bluetooth.

I am using these Bluetooth temperature sensors with massive batteries and an ESP32 outside reading them and through which they connect to Home Assistant. I have two in the refrigerator and one in the freezer.