滴管眼部滴管，舌滴，试管滴管，培养皿滴管，随时滴管。使用这个3." glass dropper, with a rubber squeeze bulb to drop small amounts of liquid wherever you think they should go. You will have to measure by counting drops, though, because there are no markings on it. Also, it is called "3" because that is about how long the glass tube is. Overall, it is 4" long.