Mine has a little black rubber gasket do I guess the 2nd one. I didn't look that closely to the pic. Sorry, I posted a picture above on this thread with mine on a water bottle. I don't do anything to keep it from leaking it just doesn't leak. Maybe the little rubber part? I puncture a small pin hole in the top of the water bottle so the water will continue to flow when the chicks peck at itI'm sorry I don't understand your reply? Are yours the 1st, 2nd, or 3rd picture? How do you keep the bottle from leaking? Thank you.