Neewer Complete Neutral Density Filter Kit for Cokin P Series Filter System:Full ND Filter Set(ND2,ND4,ND8,ND16)+Graduated ND Filter Set(G.ND2,G.ND4,G.N8,G.ND16)+Adapter Rings+Filter Holder Kit includes:(4)Full ND Filter Set(ND2, ND4, ND8, ND16) + (4)Graduated ND Filter Set(G.ND2, G.ND4, G.N8, G.ND16) + (9)Metal Adapter Rings(49mm, 52mm, 55mm, 58mm, 62mm, 67mm, 72mm, 77mm, 82mm) + (1)Square Filter Holder + (1)Filter Carrying Pouch. The full ND filters(ND2, ND4, ND8, ND16)reduce the amount of light reaching the film without affecting the color. Can be used to enable slower shutter speeds. The graduated ND filters(G.ND2, G.ND4, G.N8, G.ND16)are a MUST for digital users, because the digital sensor unlike film has very low exposure tolerance. Detail will be lost on both low and high light area. To correct this, you need graduated filters to balance it! The 49-82mm adapter rings are made of high quality anodized black aluminum(metal). The square filter holder allows for creative use of light correction or special effects.