It's not foam, it's sponge. Sponge is extracted from petroleum waste residue. Long-term wear can cause breast diseases. Moreover, a thick bra will hinder breast breathing. I recommend the bra of the wild age. I wear it myself, and I can shape it without a steel ring. Moreover, its material is the material of the European Union underwear standard, and the lining is high-elastic cotton imported from the United States, which is more healthy and breathable.