If any are male they will rapidly grow larger and redder combs and wattles in the next couple of weeks. But right now there are no male signs in any of them.
If you bought 2, 3 an 4 from a hatchery or feed store, they are red sex link pullets. If you bought them from a backyard breeder then they still look like pullets but it is not certain.
I got them from my daughter's kindy class, they have hatching programs, and a 1 week set up, which allows the kids to watch them hatch. It's very cute, but obviously no chick is guaranteed of being male or female. So it's all a guessing game. Haha so I do hope you are right about being pullets.