Features View temperature and water level: This meter monitors the tank liquid depth level, and view the temperature of your room, the temperature of the water tank and the water level (represented by a bar graph of 10 elements) Transmission frequency: The transmission frequency of the liquid level sensor is 433MHZ, the transmission range is 100 meters (300 feet) in an open area, and the transmission interval is the level change of 30s or the level unchanged for 3 minutes Indoor observation: Ultrasonic water tank liquid depth water level sensor allows you to pay close attention to your outdoor water tank in your own comfortable living room, with an effective distance of up to 100m. Easy to install: You can hang the receiver unit on the wall or pull out the bracket and place it on the kitchen countertop, table or desk. Or hang on the wall. Simultaneous display: Water level sensor transmitter can display indoor temperature (℉ or ℃) and water tank temperature (℉ or ℃) at the same time. Temperature accuracy ±1℃ Description: Keep an eye on your outdoor water tank from the comfort of your own living room, up to 100m away. Installed at the top of your water tank, the transmitter unit measures the water level using an ultrasonic sensor and temperature using a thermo sensor.  Specification: Indoor Temperature Range: 0~60℃ Outdoor Temperature Range: -40~60℃ Temperature Accuracy: ±1oC Water Level Measure Rang: 0~15m             Resolution: 0.01m             Accurate: +/-0.03M Transmission Frequency: 433MHZ Transmission Range: 100 meters(300 feet)in open area Transmission Interval: 30s when level changes or 3 minutes when level does not change Receiver Battery: 2X AA 1.5V LR3 Alkaline batteries (Not included) Transmitter Battery: 6X AAA 1.5V LR6 Alkaline or lithium batteries (Not included) Battery Life: Minimum 12 months for receiver                   Minimum 12 months for transmitter Receiver Size: 108*94*27mm Transmitter Size: 97*68*152mm LCD Size: 66*45mm(3.3 inch) Suitable Liquid Type: All non-corrosive liquid Open Distance: Approx.100M/328.1ftEffective Distance : Approx.30M/98.4ft Package Includes: 1 x Water Level Sensor Transmitter 1 x Indoor Receiver 2 x Screws (Batteries are NOT included) Note: 1. Install the battery in the battery compartment of the transmitter, do not insert the battery compartment, and insert the battery synchronously after the receiver is set up 2. The liquid level indicator has no data, press the tank key, and the data will be displayed.3. When reset, remove the battery Wait for a while and then turn on the power to eliminate the remaining power in the machine.4. Whether the red light of the transmitter flashes, the flashing is normal, and vice versa. Package List