The Women's History site offers a concise description of Firestone's activism:
Shulamith Firestone helped create several radical feminist groups. With Jo Freeman she started The Westside Group, an early consciousness-raising group in Chicago. In 1967, Firestone was one of the founding members of New York Radical Women. When NYRW split into factions amid disagreement about what direction the group should take, she launched Redstockings with Ellen Willis.Kind of makes you cringe, doesn't it, reading about that hearing on abortion. We're now back to talking about contraception-- only with men only, not even nuns allowed to talk.
The members of Redstockings rejected the existing political left. They accused other feminist groups of still being part of a society that oppressed women. Redstockings drew attention when its members disrupted a 1970 abortion hearing in New York City at which the scheduled speakers were a dozen men and a nun. Redstockings later held its own hearing, allowing women to testify about abortion.