ND(Neutral Density) filter Material:Made of optical glass Sizes :37 49 52 55 58 62 67 72 ... 77(mm) Models:ND2,ND4,ND8,ND16,ND32 Optical ND(Neutral Density) filter 1.This products is used to reduce the amount ... .We owns our owned factory,and specialising in producing ND filter many years,So,donot worry about the quality,and our ...