They connect to almost any pump and best of all. You can drive comfortably with them on. I am exclusively pumping and that takes up so much of my day. I don’t have to plan around pumping as much as I did before. Nighttime feedings are great. I can bottle feed my son WHILE pumping. Instead of feeding, burping, laying down, pumping. I can save myself 25 mins which equals more sleep for me. Each cup hold 8oz so 16 all together. It also comes with two flange sizes -25 mm and 28. So if anyone has bee wondering if they’re worth it. They totally are in my opinion! (: