We have developed this special feeder item from a medical device. We can feeding with it precisely in test tubes even if full with workers. With the flexible tube you can reach even the most unattainable areas, and can inject tiny, 1mm or smaller drops on the side of the test tube. It's very helpful with smaller species, which can stick into the bigger drops and die. Another benefit, if you feeding with this tool, your honey-expenditure will much more economical. Can feed as much as the ants need, don't have to wipe, and throw out the unnecessary quantity.