39mm Universal Air Filter Cleaner Scooter Motorcycle ATV 50cc 125cc 150cc FITS 38/39/40mm Carburetor Opening (Intake Side) High Air Flow with Excellent Filtration Materials. Added Value: Comes with Clamp, Easy to Install and Maintain. Higher air flow than normal filter for maximum power. Pliable flanges absorb vibration and can be stretched up to 1/16 In. to fit in-between sizes.