🌠The pump only works if the target container is less than the source container. When the liquid comes close you can pinch the hose and remove the hand pump that holds the hose end in the target container. Rubber hand pump that quickly starts siphoning liquid flow. Hand pump for petrol, oil, air, water and other common liquids ideal for emergency gas transfer. You don’t have to start the siphoning process with your mouth. Never start the siphoning process with your mouth, it is extremely dangerous and highly inefficient. Not suitable for drinking water, salt water and any chemical and corrosion liquids.