Power and communication indicator lights;5000 FT (1500 m) open range;Long battery life (minimum 10 years) with included 1.5V Lithium AA batteries;Transmitter temperature range of -40 degrees F to 140 degrees F (-40 degrees C to 60 degrees C);10K (type 2 and 3), 5K, 12K and 20K resistance setting options;Compatible with all tekmar controls and thermostats as well as other manufacturers products;8 walls / 250 ft. (75 m) indoor range;Low transmitter battery status indicator on the receiver