There are only two nursing supplementers available in the USA, which are intended for use by adoptive mothers, the Lact-Aid Nursing Trainer and the Medela Supplemental Nursing System
Medela Supplemental Nursing System:
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Search online, you will find where to buy them.
Summer used Supplemental Nursing System in the very first couple of days, because she was a kind of premature baby(2 weeks earlier), and we got the Supplemental Nursing System from the hospital.