K&N adjustable Red Air Filters includes3 x flange inserts which adjust the filter's flange to one of three inside flange diameters. The flange pod filterflanges are made with ultra-strong molded pliable rubber which absorbs vibration and allows for secure attachment. K&N clamp-on universal air filters are washable and reusable.

Part RG-1001RD Product Specifications
Base Outside Diameter: 6 in (152 mm)
Top Outside Diameter: 4.75 in (121 mm)
Flange Type: Centered
Height: 5.5 in (140 mm)
Filter Material: Cotton Gauze
Top Style: Metal
Top Material/Finish: Chrome
Color: Red
Weight: 1.7 lb (0.8 kg)

Flanges:
Flange Inside Diameter with no insert is: 4 in (102 mm)
Flange Inside Diameter with adjustable insert is: 3.5 in (89 mm)
Flange Inside Diameter with adjustable insert is: 3 in (76 mm)
Flange Length: 1.125 in (29 mm)