Functions: The gauge monitors the depth level of the liquid in the tank and displays on a 10-element LCD bar graph. Can keep minimum / maximum records of liquid level in the tank. Supports tank high / low liquid level alarm and tank empty liquid alarm. It displays both the inside temperature ( or ) and the temperature of the tank ( or ) at the same time. The receiver can be placed on a desk or hung on a table Specification: Indoor temperature range: 0 ~ 60 Outdoor temperature range: -40 ~ 60 Temperature accuracy: 1oC Water level measuring range: 0 ~ 15m Resolution: 0.01 m Exact: +/- 0.03M. Transmission frequency: 433MHZ Transmission range: 100 meters (300 feet) in open space Transmission interval: 30s when the level changes or 3 minutes when the level does not change Receiver battery: 2 AA 1.5V LR3 alkaline batteries (not included) Transmitter battery: 6 x AAA 1.5V LR6 Alkaline or Lithium batteries (not included) Battery life: minimum 12 months for the receiver Minimum 12 months for the transmitter Receiver size: 108 * 94 * 27mm Transmitter size: 97 * 68 * 152mm LCD size: 66 * 45mm (3.3 inch) Suitable type of fluid: All non-aggressive liquids Ultrasonic Liquid Level Gauge 433MH 15M Package includes: 1 x Water Level Sensor Transducer 1 x internal receiver 2 x screws (Batteries are NOT included)