The specific operation methods of the bottle-top dispenser are as shown below: 1. Insert the intake pipe and tighten the nut. 2. Insert and tighten the drain pipe. 3. Opening the cap and place the cap under the drainage pipe. 4. Adjust the volume of liquid separation from zero to the corresponding value by rotating the scale. 5. Exhaust process: Make sure that the cover of the drain pipe is opened and the piston is lifted a certain distance. Then press down and repeat the step 1-2 times. Stop when the bubble is completely eliminated through the observation window. 6. Preparing for liquid separation after exhaust. (Note: If the exhaust has not been completely exhausted, please check whether the suction pipe or other valves are installed correctly.) 7. Adjust the volume of liquid separation from zero to the corresponding value by rotating the scale. 8. After using it, the first step is to press the piston to the bottom, then adjust the knob to zero scales and lock the bottle mouth distributor. 9. Transfer process: lift the piston stably to the top, then press the piston equally stable to the bottom, so as to complete a liquid separation process.