Rittal Fan Filter Exhaust The Rittal fan filter exhaust is used for ventilation by convection. The outlet filter can be installed in the upper and lower sections of the enclosure. The filter frame is made of ABS material. The filter is made of chemical fibre material. The filter is available with a length of 323mm and a width of 323mm. It is suitable for 292mm x 292mm fan size. Certifications Material resistance to UL 94-5VA ANSI/ESD S20.20:2014 BS EN 61340-5-1:2007