Fits for Freeway Freeway 2 Head circumference in cm Helmet size Tighten Standard Looser 54 XS 3.5cm 30 mm 25 mm 20 mm 55-56 S 3.5cm 30 mm 25 mm 20 mm 57-58 M 3.5cm 30 mm 25 mm 20 mm 59-60 L 3.5cm 30 mm 25 mm 20 mm 15 mm 61-62 XL 3.5cm 30 mm 25 mm 20 mm 15 mm 63-64 XXL 3.5cm 30 mm 25 mm 20 mm 15 mm