Medela Bottle Nipple Ring

This is a direct replacement for the yellow ring that holds the silicone nipple on a Medela brand bottle. It's almost identical, but the top surface is optimized for printing the part upside down (it's flat). Unfortunately, that means the clear covers don't have a place to snap on over the nipple.

UPDATE 2017-09-14: By request I have added a 'beefy' version with walls 1.5 mm thicker, as well as the STEP file for the original in case you want to make your own mods.