This is a "slim type" nipple brush I purchased last year. It's a perfect fit for the slim type of the Pigeon Mother's Milk nipple! I was also using it for the regular size of the Pigeon Mother's Milk nipple. I bought too many, so I'm selling a new, unopened one. If you leave a comment, I'll include one unused brush (outer bag opened) as a bonus. Since it's a set of 2, I have an extra... Please let me know if you'd like it!