Chick one ( darker brown and slightly larger)
My Flock includes :
http://www.backyardchickens.com/a/da-bator (My incubator Build)
There are a lot of breeds that look like that as chicks. Far too many to even try to guess. Post again once they are feathered in.
The suspense is killing me . I need to get rid of a few but I don't want to get rid of the wrong ones