Removable 3m lead with probe. Max/Min and In/Out temperature and humidity recall feature with reset. Indoor range: 32¡ãF to 122¡ãF (0¡ãC to 50¡ãC). Outdoor range: -58¡ãF to 158¡ãF (-50¡ãC to 70¡ãC). Humidity: 15% to 95%. Operates on (1) "AAA" battery (included). Dimension: 4" (W) x 4 1/4" (H) x .1" (D).