Buy this replacement part for your broken Maymom, spectra or nenesupply backflow protector for the inner case (small case). This is only PART of the backflow protector, not the whole backflow protector. REMINDER: when installing/removing the backflow protector, TURN to insert/remove; do not use strong force to insert or pull to prevent from damaging the small case. Contains 2pc; inner case only, not the whole backflow protector BPA free. Short stem Small case (Aka Inner Case) for Maymom, Spectra Backflow