Troy Lee Design D3 helmet sizing

The D3 XL and 2XL helmets have the same size shell. The 2XL has thinner 15mm cheek pads and a 10mm liner, while the XL has 20mm cheek pads and a 15mm liner.

Cheek pad sizes:
XS: 30mm
SM: 25mm
MD: 20mm
LG: 15mm
XL: 20mm
2XL: 15mm

In addition, there are apparently two different type of cheek pads sold as D3 cheek pads. I'm not sure why there are two, but the bottom one in the picture is what fits current (as of 2018) D3 helmets, while the top one fits much looser and leaves velcro exposed in the helmet.

Top: Aftermarket cheek pad
Bottom: Stock cheek pad

Burton Channel screws

It takes 8 turns to thread a screw to the bottom of a Burton Channel insert. When mounting bindings, count your turns to insure you don't thread it past the bottom of the inert and into the Channel itself.