The cokin gradual nd kit plus holder h3h0 25 contains the nd2 filter p121l with 1 stop density and hard edged transition the nd4 filter p121m with 2 stop density and hard edged transition and the nd8 filter p121s with 3 stop density and soft edged transition also included in this kit is a p series filter holder measuring 84x84mm meaning that the only extra thing youll need to get started is an adapter ring the diameter of which will depend on which lens you are using