Filter 725 a2 designed to protect against organic gases and vapors from chemical compounds with a boiling point above 65 °c (type a). manufactured with a bell-shaped plastic casing to foster a more efficient and comfortable airflow during breathing. features a standard din en 148-1 (rd40) thread connection, compatible with climax full face masks 731-s, 731-c, 741 and equipment with normalized en 148-1 connection. standard en 14387:2004+a1:2008