The 820 half mask has been designed to provide maximum protection against gases, vapours, and particles such as dust, mist and smoke. The half mask is compatible with filters Climax mod. 757.Main body of the half mask: Made  of  TPE  with  a  design  that  allows  it  to  adjust  to  the  face  in  an  airtight  manner,  preventing  air  from  leaking  into  the  interior  through  the  face/mask  join.  The  main  body  houses  the  two  filter  connectors  and the exhaling valve.Exhaling valves:The half mask is fitted with an exhaling valve made up of a valve-holder and a membrane, which makes it easier for exhaled air to escape.Fastening harness:It  has  a  comfortable  neck  strap  and  head  strap  that  can  be  easily  adjusted to the right length. Nominal protection factor (NPF): 50