Highly visible, ultra-bright blue LED display can be seen from across any room. When used submerged it displays the water temperature in your tank or secure it outside to display the air temperature. Uses include fresh or saltwater applications and reptile tanks. Our sensor is accurate and dependable. The Lifegard LED Digital Thermometer features an adjustable suction cup attachment and includes a safe, 6V power supply with 5? cord and a hang or stand clam shell display with complete instructions.