The Synergy Gold Portable utilizes a separate motor for each breast. Because of this, moms can now conveniently and effectively double-pump anywhere without compromising suction, leading to more productive pumping sessions. Important note regarding this upgrade breast pump: The Spectra Synergy Gold Portable is a breast pump model that includes upgrade features such as a rechargeable battery or other convenience items. Insurance covers a portion of the cost of this pump, but you are responsible for paying the remainder.