High performance DNA air filter, the best on the market for RACER use and Cafè Racer customizations, selected for you by caferace.it Features Inlet diameter: 38 mm Design: Hexagonal Length: 68 mm Large External Diameter: 101 x 76 mm Small External Diameter : 81 x 58 mm Flange: 16 mm Top Style: rubber Click on the top window (instructions) to see the technical characteristics