FOTGA 77mm Adapter + Colour Filter Holder for Cokin P series The adapter and filter holder is used for setting the filters onto the camera. 3 slots for square filter The adapter ring made of metal, the holder made of plastic Package included: 77mm Ring Adapter x1 Filter Holder x1(Note:the filters are not included) How to use: 1. Screw the ring adapter onto your lens. 2. Slide the filter holder on the ring adapter until it snap in place 3. Slide the filter into one of the filter holder slots which is depended by your filter's size. cokin p filter