Smith Helmet Size Chart
| Size | Head Circumference |
| Small | 51 - 55cm |
| Round Contour Fit Small | 55 - 59cm |
| Medium | 55 - 59cm |
| Round Contour Fit Medium | 59 - 63cm |
| Large | 59 - 63cm |
| Round Contour Fit Large | 63 - 67cm |
| X-Large | 63 - 67cm |
| Size | Head Circumference |
| Small | 51 - 55cm |
| Round Contour Fit Small | 55 - 59cm |
| Medium | 55 - 59cm |
| Round Contour Fit Medium | 59 - 63cm |
| Large | 59 - 63cm |
| Round Contour Fit Large | 63 - 67cm |
| X-Large | 63 - 67cm |