For field-installation atop XPert Balance Filtered Systems and XPert Bulk Powder Filtered Systems. Provide a second level of HEPA Filtration to meet United States Pharmacopeia (USP) <800> standard for redundant HEPA Filter in series. Each Kit includes one HEPA Filter, set of bag and straps for bag-in/bag-out system, complete metal support system, as well as certifier installation instructions. Kit adds 12.9" inches to height of an existing System.