Standard:RD40 connection in compliance with the EN148 - Particle filters efficiency (EN143) - EN14387 (Gas/vapours and combined filters for respiratory with negative pressure)- Conformed to the requirements of the European Community Directive 89/686/EEC (Personnal Protective Equipment), belongs to the EC Category III and is CE marked, followed by the identification of the certification body (0194), which assure the quality control (according to the article 11B)Protection Type: CombinationConnection Type: RD40Protection Level: P3 Class 3Material: special aluminium alloy with PE cover activated and impregnated charcoal without chrome Ø 106mm