Ferrous sulphate heptahydrate The products are mainly used in experiments andtesting.The mainly specification is as follows, CONTENT98%MIN FE 20%MIN Pb 8PPM MAX Insoluble matter in water 0.3%MAX Cd 2PPM MAX As1 PPM MAX Mm 0.05% Fe 3+0.02% packing in 25kg pp bag with one pe bag inside.