Ladies I found a way to upgrade the bottle! I put the nuk nipple upside down then screwed the lid on, so much better to fit in the milk cooler! Then I added a Dr. brown handle sleeve to make it easier to grab! Does not come off easy!
You can use the Momcozy bottles as a sippy cup in a way with the NUK sippy nipple. Fits perfect in the ring with no leaks or spills. When I travel with everything, I stack the bottles and put the nipple on top until I’m ready to use. I pour my milk in the glass bottle to store and use the empty plastic bottle for him to drink out of. You can also stack both Momcozy bottles and nipple, a more snug fit but the cooler lid still screws on.