This document describes a circuit that indicates the level of water in an overhead tank and provides an alarm when the tank is full. It works by using wires placed at different levels in the tank - when water reaches a wire, it closes a switch and turns on an LED to show the water level. When the tank is full and water reaches the top wire, it activates a transistor which sounds an electric buzzer as an alarm. The document explains the components used, including LEDs, resistors, transistors, buzzers, and how they are assembled and soldered onto a printed circuit board. The overall purpose is to allow monitoring of the water level remotely without needing to check the tank directly.