Youha Wide to Narrow Bottle Adapters allow you to use Youha wide-neck breast shields on narrow-neck bottles like Medela. Now you can use Youha The One Breast Pump with narrow-neck bottles like Medela. Using this bottle adapter, you can connect Youha wide-neck flanges to Medela bottles, so you can now pump with Youha The One directly into your Medela bottles. Includes 2x bottle adapters Pump from wide-neck breast pumps to narrow-neck bottles Wide to Narrow: use with wide-neck breast shields and narrow-neck bottles ForYouha The One Double Electric Breast Pump (click here) Compatible with breast pumps with wide-neck flange connectors: e.g. Youha One, Spectra and Philips Avent Compatible with narrow-neck bottles (e.g. Medela)