Icon Helmet Sizing Chart:

Icon provides this chart which gives a recommended helmet size based upon a hat size or a head circumference measurement:
1. Wrap flexible tape measure approximately 1 inch above eyebrows and ears
2. Use this measurement to find your size on the chart to the below
Size Hat Size Measurement
XSmall 6 5/8 – 6 1/2 20 7/8 – 21 1/4
Small 6 7/8 – 7 21 5/8 – 22
Medium 7 1/8 – 7 1/4 22 3/8 – 22 3/4
Large 7 3/8 – 7 1/2 23 1/3 – 23 1/2
XLarge 7 5/8 – 7 3/4 24 – 24 3/8
XXLarge 7 7/8 – 8 24 3/4 – 25 1/8
3XLarge 8 1/8 – 8 1/4 25 1/2 – 26
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