Spectra Dual Compact Breast PumpThe Spectra Dual Compact Breast Pump is designed to accommodate to your lifestyle. Thanks to its compact design and built in rechargeable battery, you can pump anytime, anywhere. Choosing the right size breast shield flange Using the wrong sized flange results in a painful and uncomfortable pumping experience and can make your very expensive pump produce as much milk as if you were using an $80 no brand pump. Breast shield sizing is more of an art