Description : Sensitive water alarm with 50cm water level detector wire , when there is water flow through the floater of wire , the alarm will generate a loud alarm sound ( 120 - 130db ). WORKING PRINCIPLE : There is a floating ball on the alarm , which can be used to detect the water level . When the water level is higher than this position or lower than this position , an alarm sound will be given . When the water level is higher than this position , it is a full water reminder . When the water level is lower than this position , it is a water shortage reminder . Battery operated , powered by 9V battery ( not included ). No need wiring , comes with adhesive tape , easy to install , just place the alarm to where you want . Suit for machine room , swimming pool , water tank , aquarium tank , water purifier , etc . Specification : Material : Plastic Alarm Size : Approx . 9 . 7x4 . 5x2 . 2cm / 3 . 82x1 . 77x0 . 87 inches Wire Length : Approx . 50cm / 19 . 69 inch Power : 9V Battery ( Not Included ) Floater Length : Approx . 5cm / 1 . 97 inches Package Includes : 1 Piece Water Sensor Alarm Note : Since the size above is measured by hand , the size of the actual item could be slightly different from the size above . Due to the lighting effects , monitor settings , etc . There could be some slight difference in the color of the pictures and the actual item .