80% of the flanges pn the market are compatible with all two pice pumps. Anything from maymom will work.

If you have elastic nipples you might want to try the mymom comfy or crater series flanges they have extra long tunnel to help with the nipple stretch.

https://www.amazon.com/gp/aw/d/B0B3R785HH/ref=ox_sc_act_image_6?smid=A126H4IJ9H7UJO&psc=1&th=1

Also lacktech is a game changer, long tunnel and soft silicone.

https://www.lacteck.com/store/products/4th-gen-babymotion-flange-one-pair

I also have elastic nipples.