Fly Racing Dirt Formula Cheek Pads 2018+ Fly Racing Dirt Formula Helmets replacement cheek pads. Compatible with 2018 year models and newer. OEM cheek pad sizing: XS: 55mm (also fits SM 45mm or SM 35mm) SM: 45mm (also fits XS 55mm or SM 35mm) MD: 45mm (also fits LG 35mm or LG 25mm or MD 55mm) LG: 35mm (also fits MD 45mm or MD 55mm or LG 25mm) XL: 45mm (also fits 2XL 35mm or 2XL 25mm or XL 55mm) 2Xl: 35mm (also fits XL 45mm or XL 55mm or 2XL 25mm)