GMax Adult Helmets Size Chart

GM54S Modular Street Helmet
Helmets
Size Hat Size Inches
2X-Small 6 1/2 - 6 5/8 20 7/16" - 20 7/8"
X-Small 6 3/4 - 6 7/8 21 1/4" - 21 5/8"
Small 7 - 7 1/8 22" - 22 7/16"
Medium 7 1/4 - 7 3/8 22 13/16" - 23 1/4"
Large 7 1/2 - 7 5/8 23 5/8" - 24"
X-Large 7 3/4 - 7 7/8 24 3/8" - 24 13/16"
2X-Large 8 - 8 1/8 25 3/16" - 25 5/8"
3X-Large 8 1/4 26" - 26 3/8"
4X-Large   26 1/2" - 26 5/8"

Sizing information is provided by the manufacturer and does not guarantee a perfect fit. Please use this chart as a guide only.