This sheet of IEC 60819-3 specifies requirements for four types of unfilled aramid papers:Type 1: Calendered paper.Type 2: Calendered paper, with improved tearing resistance and conformability.Type 3: Uncalendered paper.Type 4: Calendered paper, with lower density for laminating.Materials which conform to this specification meet established levels of performance. However, theselection of material by a user for a specific application should be based on the actual requirementsnecessary for adequate performance in that application and not based on this specification alone.