Construction: Made of anodised aluminum with 100% submicronic glass media formed into accordion pleats separated by aluminum separators and sealed with suitable adhesive. Testing: Tested as per FED. 209D (Particle Counter) Efficiency: 99.97% Initial Pressure Drop: 25 mm WG Nominal Rating: 0.3 micron Servicing: Hepa filters are Non-washable filter. Application: For creating highly clean enviornment, even better then CLASS 100, HEPA Filters are extensively used in: Industries: Electronics, Pharmaceutical, Precision assembly, Mechnical, Optic, Photo-film, Computer, Textile, Bewerages, Atomic, Biotech and Aeronautical Field. Laboratories: Analytical Laboratory, Biological laboratories. Research Institute: Space and Research, Educational Institute, Atomic Reseach Institute.