Quick Overview Inter Diameter: 80mm Out Diameter:200mm Feature 1. Super lip funnel, maximize intake efficiency in limited space 2. Super inner frame, 16 streamline frames, lightweight and guide air flow smoothly 3. Super filter, 3 layer dry filter, long life type filter. Intake efficiency, dust collection performance and replacement cycle are highly balanced 4. Frame Support, fits to aluminum back plate softly, also be a guide for filter to surface of th hemisphere that make easy for replacement work of the filter Filter element can be purchaseed separately from our company!