Check the listing for details. OPS-CORE FAST SF CARBON HELMET SYSTEM XLarge Tan Vented Lux Liner With OCC Dial. Condition: New. Listed at 599.99 USD. Lightweight Modular Bungee Shroud (MBS) reduces snag hazards and features carabiner clips to improve NVG retention and stability while reducing interference with other rail-mounted accessories PowerPath™ ARC™ Rail system provides a lightweight mounting solution for Ops-Core headborne ecosystems Vented Lux Liner with Occ-Dial Universal Fitband offers comfort and ventilation Head-Loc retention Chinstrap maintains security and stability External VELCRO® Brand loop kit allows for quick and easy attachment and detachment of headborne accessories Proprietary recessed groove accommodates over-the-head communication accessories with no interference and allows for helmet donning and doffing without headset removal Size - 23 1/4” - 24 3/8”