PUF/PIR sheet is a type of insulation material that is used to provide thermal and acoustic insulation for buildings, cold storages, and industrial applications. The sheet is made up of Polyurethane Foam (PUF) or Polyisocyanurate Foam (PIR), which are known for their excellent insulating properties. PUF/PIR sheets are widely used in various industries for insulation and are also used as core material for sandwich panels.