Series 1 appears to be just 8 figures and they are about 1 inch tall and made of a rubbery material. They come inside of a small colored ball ( several different colors but i dont think they relate to what character is inside ) that opens like plastic easter eggs do. Its about the size of a pingpong ball. Due to this, it is a "blind" purchase. They retail for about $0.97.
My camera is broke but heres a pic from an ebay auction for one....