"Like the GP-Tech, which was the first AGV helmet to be offered in 3 shell sizes across the size range, according to the company, the T-2 also uses 3 shell sizes. Two helmet "crown" liners are available for each shell size and any of the four sizes of cheek pads can fit in any shell size for a bespoke fit.

The breakdown for the shell sizes runs like this: XXS to M; L and XL; XXL and XXXL.

The cheek pads are available in 20, 25, 30 and 35 mm thicknesses and the "crown pads" are switchable within each shell size range; for example, the slightly thicker L crown pad can be used in the XL helmet to tighten it up or the XL pad can be fitted to the L helmet. I believe what this does is allow a single shell size to be changed to another head size; i.e., the L helmet can be made into an XL and vice-versa, and different thickness cheek pads can then also be used to dial in a specific fit."

Source - http://www.webbikeworld.com/r2/moto...

Yes, to achieve a more snug fit around the face, you would purchase the cheekpads from the next size down from the helmet in which you were currently wearing.