This is the logger you need for monitoring a storeroom and comms room.
These sturdy loggers sit (or hang) in your room measuring temperatures and humidity, and automatically transmit their readings to the gateway.
They never need to be taken out of the area or connected to a computer to get you results.
The loggers are accurate to half a degree.
If the power goes out or internet connection is lost, the logger will store data (for weeks and weeks if necessary) and transmit it to the gateway when it comes back online.