heavy hammer big one size:Length * width * height ( 5.4cm*5.4cm*6.1cm) heavy hammer small one size:Length * width * height (4.9cm*4.9cm*5.3cm) 1. After passing the cable of the float switch through the convex round hole at the center of the heavy hammer, gently push the heavy hammer to make the plastic ring embedded above the round hole fall off due to the thrust of the cable head. (If necessary, the plastic ring can also be removed with a screwdriver.). Then put the fallen plastic ring on the cable and fix the weight to set the position of the liquid level. 2. Gently push the heavy hammer to pull out the cable until the center of the heavy hammer buckles the plastic ring. As long as the heavy hammer is lightly buckled on the plastic ring, it will not slip off. If the plastic ring is damaged or lost, the bare copper wire with the same diameter can be buckled into the cable Replace. 3. In use, it is better to fix the heavy hammer on the cable (the upper and lower ends are stuck) or the inner wall of the container with a copper wire or other things to prevent the heavy hammer from sliding and affecting the water level control.