3M Half Mask 4255 Reusable3M 4255 is a high quality half mask, which is designed especially for painters and workers who work with organic vapors or gases. The half mask includes two breathing valves and a pair of integrated filters a vapor filter and a particulate filter. Large carbon filters take care to neutralize harmful substances, guarantee long life and low resistance to breathing. These integrated filters cannot be purchased or changed. Sophisticated construction with