The image shows a paper declaration is applicable for a product marketed in China. In this case, product is B+W filter, as mentioned by thread starter.
Declaration comes from "China ROHS". "ROHS" means "Restriction Of Hazardous Substances". European Union is the first implemented and starts this term "ROHS". See explaination for EU's ROHS at Wikipedia and "China ROHS" at Wikipedia.
The numeral "50" in the two chasing arrows refers to the number of years the product remains environmentally friendly (or life span before the hazardous substances leak into the environment) as explained in Newark Farnell brochure.