Ultrasonic Level Sensor Water Tank Liquid Depth Meter Electronic Digital Display Receiver Transmitter for Household Use Item Type: Ultrasonic Level Sensor Material: ABS Power Supply: Receiver: 3 x AAA Battery (not included) or DC 5V Power Cable Transmitter: 6 x AAA NiMH Battery, 900mAh Each (built in) (with solar panel for automatic recharging when exposed to sunlight) Features: 1. Backlight On and Off Function 2. 12H/24H Time Format (startup default display: 0:00 24 hours) 3. Low Battery Reminder for Transmitter 4. Alarm Clock Function (startup default display: 0:00) 5. Buzzer On and Off (only affects button sound, not alarm clock sound) 6. Indoor Temperature ℃ and ℉ (Default ℃) 7. Data Signal Indicator 8. Water Tank Temperature ℃ and ℉ (Default ℃) 9. Water Tank Level Display Unit: m and ft (startup default: m) 10. High Low Water Level Alarm Mode 11. Alarm Sound On and Off Icon Display (default on) 12. Alarm Duration: 120 seconds 13. High Low Water Level Icon Display 14. Water Level Depth Shown on 10 Elements LCD Bar Graph Receiver Indoor Temperature Range: 0℃-50℃, 32℉-122℉ Transmitter Water Tank Temperature Measurement Range: -40℃-60℃, -40℉-140℉ Water Level Measurement Range: Approx. 1-5m / 3.3-16.4ft Temperature Resolution: 0.1℃, Accuracy: ±1℃ Water Level Resolution: 0.01m, Accuracy: ±0.05m Transmitter Protecting Grade: IP65 (effective guard against rain from any direction) Wireless Transmissing Frequency: 433Hz Open Distance: Approx. 100m / 328.1ft Effective Distance: Approx. 30m / 98.4ft Screen Size: 4.3 inch