Breastflow by 'the First Years' is a unique feeding system with a 2 part teat to simulate the natural feel of the breast. My 1st 2 children would not accept any bottles at all but my new baby has no trouble at all with this bottle happily switching from breast to bottle without seeming to even notice the difference. Not a cheap product I think it was £16 for 3x 6oz bottle and teat sets but to my mind well worth it for the occasional night off as she is exclusively breastfed. Currently only stocked by Mothercare since January this product was available in the USA much earlier and every review I've seen has been positive.