I have one of these as my personal DH helmet. I am a size 60, and this fits snug the way it should. Customizeable from 58-63. This will fit some larger medium heads.
ATB-1 6D double shell CARBON helmet, BRAND NEW in original box. Purchased for $600 ea and never used. There is no better concussion and head injury protection.
(1) X-Large, $299ea NEW
Used X-Large $199, near perfect condition