Range such as that is considered 'Close (0m)'. In terms of the technique, I'd much prefer if they were two separate tags for the two temperatures. You'll also have to give actual temperature measurements that the tag gives off, both in Fahrenheit and Celsius, so everyone can understand the temperature. Lastly, boost the rank up to C - Rank please since if this was placed on someone's head then they could suffer quite consequently with the burning or freezing effect.

Voided.
Due to character death.